Discussion

Failure to display the logon banner prior to a logon attempt will negate legal proceedings resulting from unauthorized access to system resources.

Fix Text

Edit /etc/issue and add one of the DoD login banners (based on the character limitations imposed by the system). DoD Login Banners: "You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions: -The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations. -At any time, the USG may inspect and seize data stored on this IS. -Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose. -This IS includes security measures (e.g., authentication and access controls) to protect USG interests--not for your personal benefit or privacy. -Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details." OR "I've read & consent to terms in IS user agreem't."

Check Content

Responsibility

System Administrator

IA Controls

ECWM-1

Discussion

Disabling accounts after a limited number of unsuccessful login attempts improves protection against password guessing attacks.

Fix Text

For Trusted Mode: Use the SAM/SMH interface or edit the /tcb/files/auth/system/default file and update the u_maxtries attribute. See the below example: :u_maxtries#3: If manually editing the file, save any change(s) before exiting the editor. For SMSE: Note: There may be additional package/bundle updates that must be installed to support attributes in the /etc/default/security file. Use the SAM/SMH interface (/etc/default/security file) and/or the userdbset command (/var/adm/userdb/* files) to update the attribute. See the below example: AUTH_MAXTRIES=2 Note: Never use a text editor to modify any /var/adm/userdb database file. The database contains checksums and other binary data, and editors (vi included) do not follow the file locking conventions that are used to control access to the database. If manually editing the /etc/default/security file, save any change(s) before exiting the editor.

Check Content

Responsibility

System Administrator

IA Controls

ECLO-1, ECLO-2

Discussion

Enforcing a delay between consecutive failed login attempts increases protection against automated password guessing attacks.

Fix Text

For Trusted Mode: Use the SAM/SMH interface to ensure that the t_logdelay setting is 4. For SMSE: There is no fix, however, there are attack mitigations to minimize risk (see mitigations).

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Responsibility

System Administrator

Mitigations

GEN000480

Mitigation Control

Attack mitigations to minimize risk: 1. Ensure that the “nodelay” parameter is not found in the /etc/pam.conf file. 2. In the file /opt/ssh/etc/sshd_config, the “MaxAuthTries” attribute must be explicitly set to “1”. This attribute controls the maximum number of authentication attempts permitted per SSH daemon connection. 3. In the file /opt/ssh/etc/sshd_config, the “MaxStartups” attribute must be explicitly set to an organization defined value of “10” (the default) or less. This attribute controls the maximum number of unauthenticated connections to the SSH daemon. 4. IPFilter DCA mode is disabled by default, and must be explicitly enabled. Set the following attribute in the /etc/rc.config.d/ipfconf file: DCA_START=1 The below /etc/opt/ipf/ipf.conf file rule specifies a connection limit of “<limit>“ for all hosts when attempting to connect to port “<sshd port>“. The “<sshd port>“ and “<limit>“ must be set to organization defined values. Per vendor documentation, this rule must be the next-to-last rule in /etc/opt/ipf/ipf.conf. The final rule in the file must define the default connection limit. See the below example for the last 2 line entries in /etc/opt/ipf/ipf.conf (note that the double quotes are for emphasis only): “pass in proto tcp from any to any port = <sshd port> keep limit <limit>“ “block in from any to any” Save the file before exiting the editor. The system should not require restarting for the new rule(s) to take effect.

Discussion

If an account is configured for password authentication but does not have an assigned password, it may be possible to log into the account without authentication. If the root user is configured without a password, the entire system may be compromised. For user accounts not using password authentication, the account must be configured with a password lock value instead of a blank or null value.

Fix Text

For Trusted Mode: Use the System Administration Manager (SAM) or the System Management Homepage (SMH) to disable null passwords and immediately expire the password for any account with a null password, forcing the user to create a password on the very next login. Alternatively, the account may also be disabled. Protected password database files are maintained in the /tcb/files/auth hierarchy. This directory contains other directories each named with a single letter from the alphabet. User authentication profiles are stored in these directories based on the first letter of the user account name. Verify that SAM/SMH has now disabled null passwords for all accounts. # grep “:u_nullpw@:” /tcb/files/auth/[a-z,A-Z] For SMSE: Use the SAM/SMH interface (/etc/default/security file) and/or the userdbset command (/var/adm/userdb/* files) to update the attribute(s). See the below example: LOGIN_POLICY_STRICT=1 ALLOW_NULL_PASSWORD=0 Note: Never use a text editor to modify any /var/adm/userdb database file. The database contains checksums and other binary data, and editors (vi included) do not follow the file locking conventions that are used to control access to the database. If manually editing the /etc/default/security file, save any change(s) before exiting the editor. Use the System Administration Manager (SAM) or the System Management Homepage (SMH) to immediately expire the password for any account with a null password, forcing the user to create a password on the very next login. Alternatively, the account may also be disabled.

Check Content

Responsibility

System Administrator

IA Controls

IAIA-1, IAIA-2

Discussion

If an account has an UID of 0, it has root authority. Multiple accounts with an UID of 0 afford more opportunity for potential intruders to compromise a privileged account.

Fix Text

Remove or change the UID of accounts other than root that have UID 0.

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

Changing the root home directory to something other than / and assigning it a 0700 protection makes it more difficult for intruders to manipulate the system by reading the files root places in its default directory. It also gives root the same discretionary access control for root's home directory as for the other plain user home directories.

Fix Text

The root home directory should be something other than / (such as /roothome). # mkdir /rootdir # chown root /rootdir # chgrp root /rootdir # chmod 700 /rootdir # cp -r /.??* /rootdir/. Edit the passwd file and change the root home directory to /rootdir. The cp -r /.??* command copies all files and subdirectories of file names that begin with "." into the new root directory, which preserves the previous root environment. Ensure you are in the "/" directory when executing the "cp" command.

Check Content

Responsibility

System Administrator

IA Controls

ECCD-1, ECCD-2

Discussion

Permissions greater than 0700 could allow unauthorized users access to the root home directory.

Fix Text

The root home directory will have permissions of 0700. Do not change the protections of the / directory. Use the following command to change protections for the root home directory: # chmod 0700 /rootdir.

Check Content

Responsibility

System Administrator

IA Controls

ECCD-1, ECCD-2

Discussion

The executable search path (typically the PATH environment variable) contains a list of directories for the shell to search to find executables. If this path includes the current working directory or other relative paths, executables in these directories may be executed instead of system commands. This variable is formatted as a colon-separated list of directories. If there is an empty entry, such as a leading or trailing colon, two consecutive colons, or a single period, this is interpreted as the current working directory. Entries starting with a slash (/) are absolute paths.

Fix Text

Edit the root user's local initialization files and remove any relative path entries that have not been documented with the ISSO. Edit the root user’s local initialization files and remove any empty entry that is defined.

Check Content

Responsibility

System Administrator

Discussion

If the root search path contains a world-writable directory, malicious software could be placed in the path by intruders and/or malicious users and inadvertently run by root with all of root's privileges.

Fix Text

For each world-writable path in root's executable search path, do one of the following: 1. Remove the world-writable permission on the directory. Procedure: # chmod o-w <path> 2. Remove the world-writable directory from the executable search path. Procedure: Identify and edit the initialization file referencing the world-writable directory and remove it from the PATH variable.

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Responsibility

System Administrator

IA Controls

ECCD-1, ECCD-2

Discussion

Limiting the root account direct logins to only system consoles protects the root account from direct unauthorized access from a non-console device.

Fix Text

If the /etc/securetty file does not exist, create the file containing only the word console and ensure correct file properties. # echo “console” > /etc/securetty

Check Content

Responsibility

System Administrator

Discussion

If a user is assigned the GID of a group not existing on the system, and a group with that GID is subsequently created, the user may have unintended rights to the group.

Fix Text

Add a group to the system (edit /etc/group) for each GID referenced without a corresponding group.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

Restricting permission on daemons will protect them from unauthorized modification and possible system compromise.

Fix Text

Change the mode of the network services daemon. # chmod 0755 <path>/<daemon>

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

If the skeleton files are not protected, unauthorized personnel could change user startup parameters and possibly jeopardize user files.

Fix Text

Change the mode of skeleton files with incorrect mode. # chmod 0444 <skeleton file>

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

NIS/NIS+/yp files are part of the system's identification and authentication processes and are, therefore, critical to system security. Failure to give ownership of sensitive files or utilities to root or bin provides the designated owner and unauthorized users with the potential to access sensitive information or change the system configuration which could weaken the system's security posture.

Fix Text

Change the ownership of NIS/NIS+/yp files to root, sys, or bin. Consult vendor documentation to determine the location of the files. Procedure (example): # chown root <filename>

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

NIS/NIS+/yp files are part of the system's identification and authentication processes and are, therefore, critical to system security. Unauthorized modification of these files could compromise these processes and the system.

Fix Text

Change the mode of NIS/NIS+/yp command files to 0755 or less permissive. Procedure (example): # chmod 0755 <filename>

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

Restricting permissions will protect the files from unauthorized modification.

Fix Text

Change the owner of system files, programs, and directories to a system account. Procedure: # chown root <path>/<system file> (A different system user may be used in place of root.)

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

Restricting permissions will protect the files from unauthorized modification.

Fix Text

Change the group owner of system files to a system group. Procedure: # chgrp root <path>/<system file> (System groups other than root may be used.)

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

The /etc/shadow file contains the list of local system accounts. It is vital to system security and must be protected from unauthorized modification. Failure to give ownership of sensitive files or utilities to root or bin provides the designated owner and unauthorized users with the potential to access sensitive information or change the system configuration which could weaken the system's security posture.

Fix Text

For Trusted Mode: # chown root /tcb # chown root /tcb/files /tcb/files/auth # chown root /tcb/files/auth/[a-z]/* For SMSE: # chown root /etc/shadow

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Responsibility

System Administrator

Discussion

If the passwd file is writable by a group owner or the world, the risk of passwd file compromise is increased. The passwd file contains the list of accounts on the system and associated information.

Fix Text

Change the mode of the passwd file to 0444. # chmod 0444 /etc/passwd Document all changes.

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Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

The /etc/shadow file contains the list of local system accounts. It is vital to system security and must be protected from unauthorized modification. The file also contains password hashes which must not be accessible to users other than root. The Trusted Mode /tcb tree requires modes more permissive than the shadow file.

Fix Text

For Trusted Mode: # chmod 0555 /tcb # chmod 0771 /tcb/files /tcb/files/auth # chmod 0664 /tcb/files/auth/[a-z]/* For SMSE: # chmod 0400 /etc/shadow

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Responsibility

System Administrator

Discussion

The umask controls the default access mode assigned to newly created files. An umask of 077 limits new files to mode 700 or less permissive. Although umask can be represented as a 4-digit number, the first digit representing special access modes is typically ignored or required to be 0. This requirement applies to the globally configured system defaults and the user defaults for each account on the system.

Fix Text

Edit local and global initialization files containing umask and change them to use 077 instead of the current value.

Check Content

Security Override Guidance

If the default umask is 000 or does not restrict the world-writable permission, this becomes a CAT I finding.

Responsibility

System Administrator

IA Controls

ECCD-1, ECCD-2

Discussion

Vendor accounts and software may contain backdoors that will allow unauthorized access to the system. These backdoors are common knowledge and present a threat to system security if the account is not disabled.

Fix Text

For Trusted Mode and SMSE: Use the System Administration Manager (SAM) or the System Management Homepage (SMH) to lock/disable or remove any enabled default system accounts.

Check Content

Responsibility

System Administrator

IA Controls

IAAC-1

Discussion

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.

Fix Text

Edit /etc/rc.config.d/auditing and add -e open to the end of the AUDEVENT_ARGS1 parameter.

Check Content

Responsibility

System Administrator

IA Controls

ECAR-1, ECAR-2, ECAR-3

Discussion

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.

Fix Text

Edit /etc/rc.config.d/auditing and add -e delete to the end of the AUDEVENT_ARGS1 parameter.

Check Content

Responsibility

System Administrator

IA Controls

ECAR-1, ECAR-2, ECAR-3

Discussion

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.

Fix Text

Edit /etc/rc.config.d/auditing and add -e admin and -e removable to the end of the AUDEVENT_ARGS1 parameter.

Check Content

Responsibility

System Administrator

IA Controls

ECAR-1, ECAR-2, ECAR-3

Discussion

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.

Fix Text

Edit /etc/rc.config.d/auditing and add -e login to the end of the AUDEVENT_ARGS1 parameter.

Check Content

Responsibility

System Administrator

IA Controls

ECAR-1, ECAR-2, ECAR-3

Discussion

If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system compromise.

Fix Text

Edit /etc/rc.config.d/auditing and add -e moddac to the end of the AUDEVENT_ARGS1 parameter.

Check Content

Responsibility

System Administrator

IA Controls

ECAR-1, ECAR-2, ECAR-3

Discussion

Failure to give ownership of sensitive files or utilities to root provides the designated owner and unauthorized users with the potential to access sensitive information or change the system configuration which could weaken the system's security posture.

Fix Text

Change the ownership of the inetd.conf file to root or bin. # chown root <file or directory>

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

The Internet service daemon configuration files must be protected as malicious modification could cause Denial of Service or increase the attack surface of the system.

Fix Text

Change the mode of the (x)inetd.conf file. # chmod 0440 <file>

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

Failure to give ownership of sensitive files or utilities to root or bin provides the designated owner and unauthorized users with the potential to access sensitive information or change the system configuration which could weaken the system's security posture.

Fix Text

Change the ownership of the services file to root or bin. # chown root /etc/services

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

The services file is critical to the proper operation of network services and must be protected from unauthorized modification. Unauthorized modification could result in the failure of network services.

Fix Text

Change the mode of the services file to 0444 or less permissive. # chmod 0444 /etc/services

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

If the mesg -n or mesg n command is not placed into the system profile, messaging can be used to cause a Denial of Service attack.

Fix Text

Edit /etc/profile or another global initialization script, and add the mesg -n command.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

Having the "+" character in the hosts.lpd (or equivalent) file allows all hosts to use local system print resources.

Fix Text

Remove the "+" entries from the hosts.lpd (or equivalent) file.

Check Content

Responsibility

System Administrator

IA Controls

ECCD-1, ECCD-2

Discussion

Failure to give ownership of the hosts.lpd file to root, bin, sys, or lp provides the designated owner, and possible unauthorized users, with the potential to modify the hosts.lpd file. Unauthorized modifications could disrupt access to local printers from authorized remote hosts or permit unauthorized remote access to local printers.

Fix Text

Change the owner of the /etc/hosts.lpd file (or equivalent) to root, lp, or another privileged UID. # chown root <print service configuration file>

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

Excessive permissions on the hosts.lpd (or equivalent) file may permit unauthorized modification. Unauthorized modifications could disrupt access to local printers from authorized remote hosts or permit unauthorized remote access to local printers.

Fix Text

Change the mode of the /etc/hosts.lpd file (or equivalent) to 0644 or less permissive. Procedure: # chmod 0644 <print service configuration file>

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

If the aliases file is not owned by root, an unauthorized user may modify the file to add aliases to run malicious code or redirect e-mail.

Fix Text

Change the owner of the /etc/mail/aliases file (or equivalent) to root. # chown root /etc/mail/aliases

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

Excessive permissions on the aliases file may permit unauthorized modification. If the alias file is modified by an unauthorized user, they may modify the file to run malicious code or redirect e-mail.

Fix Text

Change the mode of the aliases file (or equivalent) to 0644. # chmod 0644 /etc/mail/aliases

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

If a file executed through a mail aliases file is not owned and writable only by root, it may be subject to unauthorized modification. Unauthorized modification of files executed through aliases may allow unauthorized users to attain root privileges.

Fix Text

Edit the /etc/mail/aliases file Locate the entries executing a program. They will appear similar to the following line: alias: "|/usr/local/bin/ls" (or some other program name) Ensure root owns the programs and the directory(ies) they reside in by using the chown command to change owner to root. For a directory entry: # chown root <entry> For a file entry (change BOTH the directory and file, where/as necessary: # chown root <entry> # chown root `dirname <entry>`

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

If a file executed through a mail alias file has permissions greater than 0755, it can be modified by an unauthorized user and may contain malicious code or instructions possibly compromising the system.

Fix Text

Use the chmod command to change the access permissions for files executed from the aliases file. For example: # chmod 0755 <path/file>

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

If Sendmail is not configured to log at level 9, system logs may not contain the information necessary for tracking unauthorized use of the sendmail service.

Fix Text

Edit the sendmail.cf file, locate the entry (and where necessary uncomment it and/or create it) and modify/set it to 9.

Check Content

Responsibility

System Administrator

IA Controls

ECAR-1, ECAR-2, ECAR-3

Discussion

If informational and more severe SMTP service messages are not logged, malicious activity on the system may go unnoticed.

Fix Text

Edit the syslog.conf file and add a configuration line specifying an appropriate destination for critical "mail" syslogs, for example: mail.crit /var/adm/messages mail.* /var/adm/messages *.* /var/adm/messages *.crit /var/adm/messages

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

If the SMTP service log file is not owned by root, then unauthorized personnel may modify or delete the file to hide a system compromise.

Fix Text

Change the ownership of the sendmail log file. # chown root <sendmail log file>

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

If the SMTP service log file is more permissive than 0644, unauthorized users may be allowed to change the log file.

Fix Text

Change the mode of the SMTP service log file. # chmod 0644 <sendmail log file>

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

The ftpusers file contains a list of accounts not allowed to use FTP to transfer files. If this file does not exist, then unauthorized accounts can utilize FTP.

Fix Text

Create a /etc/ftpd/ftpusers (or equivalent) file containing a list of /etc/passwd accounts not authorized for FTP.

Check Content

Responsibility

System Administrator

IA Controls

ECCD-1, ECCD-2

Discussion

If the file ftpusers is not owned by root, an unauthorized user may modify the file to allow unauthorized accounts to use FTP.

Fix Text

Change the owner of the ftpusers file to root. # chown root /etc/ftpd/ftpusers

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

Excessive permissions on the ftpusers file could permit unauthorized modification. Unauthorized modification could result in Denial of Service to authorized FTP users or permit unauthorized users to access the FTP service.

Fix Text

Change the mode of the ftpusers file to 0640. # chmod 0640 /etc/ftpd/ftpusers

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

Secure mode limits TFTP requests to a specific directory. If TFTP is not running in secure mode, it may be able to write to any file or directory and may seriously impair system integrity, confidentiality, and availability.

Fix Text

Edit /etc/inetd.conf and add one path argument, representing the TFTP root directory, to the tftpd command.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

If TFTP runs with the setuid or setgid bit set, it may be able to write to any file or directory and may seriously impair system integrity, confidentiality, and availability.

Fix Text

Change the mode of the TFTP daemon. # chmod 0755 /usr/lbin/tftpd

Check Content

Responsibility

System Administrator

IA Controls

ECPA-1

Discussion

If TFTP has a valid shell, it increases the likelihood that someone could logon to the TFTP account and compromise the system.

Fix Text

Create a tftp user account if none exists. Assign a non-login shell to the tftp user account, such as /usr/bin/false. Assign/create the tftp user account home directory where/as necessary. Ensure the home directory is owned by the tftp user.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

Due to numerous security vulnerabilities existing within NIS, it must not be used. Possible alternative directory services are NIS+ and LDAP.

Fix Text

Disable the use of NIS. Possible replacements are NIS+ and LDAP-UX.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

If users do not have a valid home directory, there is no place for the storage and control of files they own.

Fix Text

For Trusted Mode: Determine why the user is not assigned a home directory. Possible actions include: account deletion or disablement. If the account is determined to be valid, manually create the home directory if required (mkdir directoryname, copy the skeleton files into the directory, chown account name for the new directory and the skeleton files) and assign to the user in the /etc/passwd file or take corrective action via the HP SMH/SAM utility. For SMSE: Note: There may be additional package/bundle updates that must be installed to support attributes in the /etc/default/security file. Determine why the user is not assigned a home directory. Possible actions include: account deletion or disablement. If the account is determined to be valid, manually create the home directory if required (mkdir directoryname, copy the skeleton files into the directory, chown account name for the new directory and the skeleton files) and assign to the user in the /etc/passwd file or take corrective action via the HP SMH/SAM utility. Additionally, use the SAM/SMH interface (/etc/default/security file) and/or the userdbset command (/var/adm/userdb/* files) to update the ABORT_LOGIN_ON_MISSING_HOMEDIR attribute. See the below example: ABORT_LOGIN_ON_MISSING_HOMEDIR=1 Note: Never use a text editor to modify any /var/adm/userdb database file. The database contains checksums and other binary data, and editors (vi included) do not follow the file locking conventions that are used to control access to the database. If manually editing the /etc/default/security file, save any change(s) before exiting the editor.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

If a user has a home directory defined that does not exist, the user may be given the / directory, by default, as the current working directory upon logon. This could create a Denial of Service because the user would not be able to perform useful tasks in this location.

Fix Text

Determine why the user home directory does not exist. Possible actions include: account deletion or disablement. If the account is determined to be valid, create the home directory either manually (mkdir directoryname, copy the skeleton files into the directory, chown account name for the new directory and the skeleton files) or via the HP SMH/SAM utility.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

Local initialization files are used to configure the user's shell environment upon login. Malicious modification of these files could compromise accounts upon logon.

Fix Text

Ensure user startup files have permissions of 0740 or more restrictive. Examine each user's home directory and verify all file names beginning with "." have access permissions of 0740 or more restrictive. If they do not, use the chmod command to correct the vulnerability. Procedure: # chmod 0740 .filename NOTE: The period is part of the file name and is required.

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

The executable search path (typically the PATH environment variable) contains a list of directories for the shell to search to find executables. If this path includes the current working directory or other relative paths, executables in these directories may be executed instead of system commands. This variable is formatted as a colon-separated list of directories. If there is an empty entry, such as a leading or trailing colon, two consecutive colons, or a single period, this is interpreted as the current working directory. Paths starting with a slash (/) are absolute paths.

Fix Text

Edit the run control script and remove the relative path entries from the executable search path variable that are not documented with the ISSO. Edit the run control script and remove any empty entry that is defined.

Check Content

Responsibility

System Administrator

Discussion

Unencrypted passwords for remote FTP servers may be stored in .netrc files. Policy requires passwords to be encrypted in storage and not used in access scripts.

Fix Text

Remove the .netrc file(s). Procedure: # rm .netrc

Check Content

Responsibility

System Administrator

IA Controls

IAIA-1, IAIA-2

Discussion

The shells file (or equivalent) lists approved default shells. It helps provide layered defense to the security approach by ensuring users cannot change their default shell to an unauthorized, unsecure shell.

Fix Text

Create /etc/shells file containing a list of valid system shells. Consult vendor documentation for an appropriate list of system shells. Procedure: Typical installed shells include: /sbin/sh /usr/bin/sh /usr/bin/rsh /usr/bin/ksh /usr/bin/rksh /usr/bin/csh /usr/bin/keysh # echo "/sbin/sh" >> /etc/shells (Repeat as necessary for all existing shell programs.)

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

The shells file lists approved default shells. It helps provide layered defense to the security approach by ensuring users cannot change their default shell to an unauthorized, unsecure shell.

Fix Text

Use the chsh utility or edit the /etc/passwd file and correct the error by changing the default shell of the account in error to an acceptable shell name contained in the /etc/shells file. Alternatively, use the HP SMH to change the /etc/passwd shell entry.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

If shell files are owned by users other than root or bin, they could be modified by intruders or malicious users to perform unauthorized actions.

Fix Text

Change the ownership of any system shell not owned by root or bin: # chown root <path/shell>

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

Shells with world/group-write permissions give the ability to maliciously modify the shell to obtain unauthorized access.

Fix Text

Change the mode of the shell. # chmod 0755 <shell>

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

System device files in writable directories could be modified, removed, or used by an unprivileged user to control system hardware.

Fix Text

Remove the world-writable permission from the device file(s). # chmod o-w <device file> Document all changes.

Check Content

Responsibility

System Administrator

Discussion

Excessive permissions on the NFS share configuration file could allow unauthorized modification of the file, which could result in Denial-of-Service to authorized NFS shares and the creation of additional unauthorized shares.

Fix Text

# chmod 0644 /etc/dfs/dfstab

Check Content

Responsibility

System Administrator

IA Controls

ECCD-1, ECCD-2, ECLP-1

Discussion

When an NFS server is configured to deny remote root access, a selected UID and GID are used to handle requests from the remote root user. The UID and GID should be chosen from the system to provide the appropriate level of non-privileged access.

Fix Text

Edit /etc/dfs/sharetab and set the anon=-1 option for shares without it. Re-export the file systems.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

The NFS access option limits user access to the specified level. This assists in protecting shared file systems. If access is not restricted, unauthorized hosts may be able to access the system's NFS shares.

Fix Text

Edit /etc/dfs/dfstab and add ro and/or rw options (as appropriate) that specify a list of hosts or networks which are permitted access. Re-share the file systems via the following commands: # unshare <the file system entry that was modified> # share <the file system entry that was modified>

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

If the NFS server allows root access to local file systems from remote hosts, this access could be used to compromise the system.

Fix Text

Edit /etc/dfs/dfstab and remove the root= option for all shares. Re-share the file systems.

Check Content

Responsibility

System Administrator

IA Controls

EBRP-1

Discussion

Enabling the nosuid mount option prevents the system from granting owner or group-owner privileges to programs with the suid or sgid bit set. If the system does not restrict this access, users with unprivileged access to the local system may be able to acquire privileged access by executing suid or sgid files located on the mounted NFS file system.

Fix Text

Edit /etc/fstab and add the nosuid option for all NFS file systems. Remount the NFS file systems to make the change take effect.

Check Content

Responsibility

System Administrator

IA Controls

ECPA-1

Discussion

Access control programs (such as TCP_WRAPPERS) provide the ability to enhance system security posture.

Fix Text

Edit /etc/inetd.conf and use tcpd to wrap active services.

Check Content

Responsibility

System Administrator

IA Controls

EBRU-1

Discussion

If access attempts are not logged, then multiple attempts to log on to the system by an unauthorized user may go undetected.

Fix Text

Configure the access restriction program to log every access attempt. Ensure the implementation instructions for TCP_WRAPPERS are followed so logging of system access attempts is logged into the system log files. If an alternate application is used, it must support this function.

Check Content

Responsibility

System Administrator

IA Controls

ECAR-2, ECAR-3

Discussion

When operating in standard mode, account passwords are stored in the /etc/passwd file, which is world readable. By operating in either Trusted Mode or Standard Mode with Security Extensions, the system security posture is enhanced thru the addition of a secure, non-world readable password container other than /etc/passwd.

Fix Text

SAM/SMH must be used to convert standard mode HP-UX to Trusted Mode (optional for SMSE). For Trusted Mode only: The following command may be used to “manually” convert from Standard Mode to Trusted Mode (note that its use is not vendor supported): # tsconvert -c For SMSE only: The following command may be used to “manually” create the /etc/shadow file with information from the /etc/passwd file (use of this commend is vendor supported). # pwconv Note that additional software bundles and/or patches may be required in order to completely convert a standard mode system to SMSE.

Check Content

Responsibility

System Administrator

IA Controls

DCSW-1

Discussion

Root, sys, and bin are the most privileged group accounts, by default, for most UNIX systems. If a file as sensitive as /etc/securetty is not group-owned by a privileged group, it could lead to system compromise.

Fix Text

Change the group-owner of the /etc/securetty to root, bin, or sys. Example: # chgrp root /etc/securetty

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

Failure to make root the owner of sensitive files and utilities may provide unauthorized owners the potential to access and/or change sensitive information or system configurations, thus weakening the overall security posture of a site.

Fix Text

Change the owner of the /etc/securetty file to root. # chown root /etc/securetty

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

Excessive permissions on the /etc/securetty file could result in unauthorized modification of the file. Changes to the file could reduce the system's security by specifying additional terminals permitted to accept root logins, or deny service by preventing root logins on authorized terminals.

Fix Text

Change the mode of the /etc/securetty file to 0640. Example: # chmod 0640 /etc/securetty

Check Content

Responsibility

System Administrator

IA Controls

ECCD-1, ECCD-2, ECLP-1

Discussion

The cron facility allows users to execute recurring jobs on a regular and unattended basis. The cron.allow file designates accounts allowed to enter and execute jobs using the cron facility. If neither cron.allow nor cron.deny exists, then any account may use the cron facility. This may open the facility up for abuse by system intruders and malicious users.

Fix Text

Create /var/adm/cron/cron.allow and/or /var/adm/cron/cron.deny with appropriate local content.

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

A cron.allow file, readable and/or writable by other than root, could allow potential intruders and malicious users to use the file contents to help discern information, such as who is allowed to execute cron programs, which could be harmful to overall system and network security.

Fix Text

Change the mode of the cron.allow file to 0600. Procedure: # chmod 0600 /var/adm/cron/cron.allow

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

To protect the integrity of scheduled system jobs and prevent malicious modification to these jobs, crontab files must be secured.

Fix Text

Change the mode of the crontab files. # chmod 0600 /var/spool/cron/crontabs/*

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

To protect the integrity of scheduled system jobs and to prevent malicious modification to these jobs, crontab files must be secured.

Fix Text

Change the mode of crontab directories to 0755.

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

Incorrect ownership of the cron or crontab directories could permit unauthorized users the ability to alter cron jobs and run automated jobs as privileged users. Failure to give ownership of cron or crontab directories to root or to bin provides the designated owner and unauthorized users with the potential to access sensitive information or change the system configuration which could weaken the system's security posture.

Fix Text

Change the mode of the crontab directory. # chown root /var/spool/cron/crontabs

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

To protect the integrity of scheduled system jobs and to prevent malicious modification to these jobs, crontab files must be secured. Failure to give group-ownership of cron or crontab directories to a system group provides the designated group and unauthorized users with the potential to access sensitive information or change the system configuration which could weaken the system's security posture.

Fix Text

Change the group owner of the crontab directories to root, sys, bin or other. # chown root /var/spool/cron/crontabs

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

Cron logging can be used to trace the successful or unsuccessful execution of cron jobs. It can also be used to spot intrusions into the use of the cron facility by unauthorized and malicious users.

Fix Text

Enable cron/logging on the system via: # /sbin/init.d/cron stop # mv <current cron log> <to a new location and new name> # /sbin/init.d/cron start # more /var/adm/cron/log Cron automatically handles its own logging function and (at least) the Start Time should be visible at the beginning of the new log file /var/adm/cron/log.

Check Content

Responsibility

System Administrator

IA Controls

ECAR-1, ECAR-2, ECAR-3

Discussion

Cron logs contain reports of scheduled system activities and must be protected from unauthorized access or manipulation.

Fix Text

Change the mode of the cron log file. # chmod 0600 /var/adm/cron/log

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1, ECTP-1

Discussion

The at facility selectively allows users to execute jobs at deferred times. It is usually used for one-time jobs. The at.allow file selectively allows access to the at facility. If there is no at.allow file, there is no ready documentation of who is allowed to submit at jobs.

Fix Text

Create at.allow and/or at.deny files containing appropriate lists of users to be allowed or denied access to the at facility supported by the cron daemon.

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

On some systems, if there is no at.allow file and there is an empty at.deny file, then the system assumes everyone has permission to use the at facility. This could create an insecure setting in the case of malicious users or system intruders.

Fix Text

Add appropriate users to the at.deny file, or remove the empty at.deny file if an at.allow file exists.

Check Content

Responsibility

Information Assurance Officer

IA Controls

ECLP-1

Discussion

Default accounts, such as bin, sys, adm, uucp, daemon, and others, should never have access to the at facility. This would create a possible vulnerability open to intruders or malicious users.

Fix Text

Remove the default accounts (such as bin, sys, adm, and others) from the at.allow file.

Check Content

Responsibility

System Administrator

IA Controls

ECPA-1

Discussion

Permissions more permissive than 0600 (i.e. read, write and execute for the owner) may allow unauthorized or malicious access to the at.allow and/or at.deny files.

Fix Text

Change the mode of the at.allow file. # chmod 0600 /var/adm/cron/at.allow

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

The snmpd.conf file contains authenticators and must be protected from unauthorized access and modification.

Fix Text

Change the mode of the SNMP daemon configuration file to 0600. # chmod 0600 /etc/SnmpAgent.d/snmpd.conf

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

The ability to read the MIB file could impart special knowledge to an intruder or malicious user about the ability to extract compromising information about the system or network.

Fix Text

Change the mode of MIB files to 0640. # chmod 0640 <mib file>

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

INN servers access Usenet newsfeeds and store newsgroup articles. INN servers use the Network News Transfer Protocol (NNTP) to transfer information from the Usenet to the server and from the server to authorized remote hosts. If this function is necessary to support a valid mission requirement, its use must be authorized and approved in the system accreditation package.

Fix Text

Disable the INN server.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

The /etc/smb.conf file allows access to other machines on the network and grants permissions to certain users. If it is owned by another user, the file may be maliciously modified and the Samba configuration could be compromised.

Fix Text

Change the ownership of the smb.conf file. # chown root /etc/opt/samba/smb.conf

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

If the smb.conf file has excessive permissions, the file may be maliciously modified and the Samba configuration could be compromised.

Fix Text

Change the mode of the smb.conf file to 0644 or less permissive. # chmod 0644 /etc/opt/samba/smb.conf

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

Samba increases the attack surface of the system and must be restricted to communicate only with systems requiring access.

Fix Text

Edit the smb.conf file and set the hosts option to permit only authorized hosts access Samba. An example might be: hosts allow = 127.0.0.1 192.168.2.0/24 192.168.3.0/24 hosts deny = 0.0.0.0/0 The above will only allow SMB connections from the localhost and from the two private networks 192.168.2 and 192.168.3. All other connections will be refused as soon as the client sends its first packet.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

Even though communications are encrypted, an additional layer of security may be gained by extending the policy of not logging directly on as root. In addition, logging in with a user-specific account preserves the audit trail.

Fix Text

Edit the configuration file and set the PermitRootLogin option to no.

Check Content

Responsibility

System Administrator

IA Controls

ECPA-1

Discussion

If the group-owner of the smb.conf file is not root or a system group, the file may be maliciously modified and the Samba configuration could be compromised.

Fix Text

Change the group owner of the "smb.conf" file. # chgrp root /etc/samba/smb.conf

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

To ensure the root shell is available in repair and administrative modes, the root shell must be located in the / file system.

Fix Text

Change the root account's shell to one present on the / file system.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

If graphical desktop sessions do not lock the session after 15 minutes of inactivity, requiring re-authentication to resume operations, the system or individual data could be compromised by an alert intruder who could exploit the oversight. This requirement applies to graphical desktop environments provided by the system to locally attached displays and input devices as well as to graphical desktop environments provided to remote systems, including thin clients.

Fix Text

Configure the CDE lock manager to lock your screen after a certain amount of inactive time. To configure the CDE lock manager to lock the screen after 15 minutes of inactive time, enter the following commands (ensure to NOT overwrite an existing file): # cp /usr/dt/config/C/sys.resources /etc/dt/config/C/sys.resources # vi /etc/dt/config/C/sys.resources Locate and add/uncomment/change the line to N=15 dtsession*lockTimeout: <N> dtsession*lockTimeout: 15 Log out of CDE and log back in to verify the timeout is in effect.

Check Content

Responsibility

System Administrator

Discussion

If a user, or root, used the same password continuously or was allowed to change it back shortly after being forced to change it, this would provide a potential intruder with the opportunity to keep guessing at one user's password until it was guessed correctly.

Fix Text

For Trusted Mode: Use the SAM/SMH interface or edit the /etc/default/security file and update the PASSWORD_HISTORY_DEPTH attribute. See the below example: PASSWORD_HISTORY_DEPTH=5 If manually editing the file, save any change(s) before exiting the editor. For SMSE: Note: There may be additional package/bundle updates that must be installed to support attributes in the /etc/default/security file. Use the SAM/SMH interface (/etc/default/security file) and/or the userdbset command (/var/adm/userdb/* files) to update the PASSWORD_HISTORY_DEPTH attribute. See the below example: PASSWORD_HISTORY_DEPTH=5 Note: Never use a text editor to modify any /var/adm/userdb database file. The database contains checksums and other binary data, and editors (vi included) do not follow the file locking conventions that are used to control access to the database. If manually editing the /etc/default/security file, save any change(s) before exiting the editor.

Check Content

Responsibility

System Administrator

IA Controls

IAIA-1, IAIA-2

Discussion

The minimal set of auditing requirements necessary to collect useful forensics data and provide user help when violations are detected must be configured.

Fix Text

Edit the /etc/rc.config.d/auditing file and insert the following line: AUDOMON_ARGS=“-p 20, -t 1, -w 90” Restart auditing: # /sbin/init.d/auditing stop # /sbin/init.d/auditing start

Check Content

Responsibility

System Administrator

IA Controls

ECAR-1, ECAR-2, ECAR-3

Discussion

SSHv1 is not a DoD-approved protocol and has many well-known vulnerability exploits. Exploits of the SSH daemon could provide immediate root access to the system.

Fix Text

Edit the configuration file and modify the Protocol line entry to appear as follows: Protocol 2

Check Content

Responsibility

System Administrator

IA Controls

DCPP-1

Discussion

File system journaling, or logging, can allow reconstruction of file system data after a system crash, thus, preserving the integrity of data that may have otherwise been lost. Journaling file systems typically do not require consistency checks upon booting after a crash, which can improve system availability. Some file systems employ other mechanisms to ensure consistency which also satisfy this requirement.

Fix Text

Implement file system journaling for the root file system, or use a file system that uses other mechanisms to ensure file system consistency. If the root file system supports journaling, enable it. If the file system does not support journaling or another mechanism to ensure file system consistency, a migration to a different file system will be necessary.

Check Content

Responsibility

System Administrator

IA Controls

ECAR-1, ECAR-2, ECAR-3

Discussion

Samba is a tool used for the sharing of files and printers between Windows and UNIX operating systems. It provides access to sensitive files and, therefore, poses a security risk if compromised.

Fix Text

If there is no functional need for Samba and the daemon is running, disable the daemon by killing the process ID as noted from the output of ps -ef |grep smbd. The utility should also be removed or not installed if there is no functional requirement.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

If file permissions for cron.deny are more permissive than 0600, sensitive information could be viewed or edited by unauthorized users.

Fix Text

Change the mode of the cron.deny file. # chmod 0600 /var/adm/cron/cron.deny

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

If the owner of the cron.allow file is not set to root, bin, or sys, the possibility exists for an unauthorized user to view or to edit sensitive information.

Fix Text

# chown root /var/adm/cron/cron.allow

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

If the at directory has a mode more permissive than 0755, unauthorized users could be allowed to view or to edit files containing sensitive information within the at directory. Unauthorized modifications could result in Denial of Service to authorized at jobs.

Fix Text

Change the mode of the at directory to 0755. # chmod 0755 <at directory>

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

If the owner of the at directory is not root, bin, or sys, unauthorized users could be allowed to view or edit files containing sensitive information within the directory.

Fix Text

Change the owner of the existing at directory to root, bin, or sys. # chown root <at directory> (Replace root with another system group and/or <at directory> with a different at directory as necessary.)

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

If the owner of the at.allow file is not set to root, sys, or bin, unauthorized users could be allowed to view or edit sensitive information contained within the file.

Fix Text

Change the owner of the at.allow file. # chown root /var/adm/cron/at.allow

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

If the owner of the at.deny file is not set to root, bin, or sys, unauthorized users could be allowed to view or edit sensitive information contained within the file.

Fix Text

Change the owner of the at.deny file. # chown root /usr/lib/cron/at.deny

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

If the group owner of the traceroute command has not been set to a system group, unauthorized users could have access to the command and use it to gain information regarding a network's topology inside of the firewall. This information may allow an attacker to determine trusted routers and other network information possibly leading to system and network compromise.

Fix Text

Change the group-owner of the traceroute command to root. See the following example: # chgrp root /usr/contrib/bin/traceroute

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

If the mode of the traceroute executable is more permissive than 0700, malicious code could be inserted by an attacker and triggered whenever the traceroute command is executed by authorized users. Additionally, if an unauthorized user is granted executable permissions to the traceroute command, it could be used to gain information about the network topology behind the firewall. This information may allow an attacker to determine trusted routers and other network information possibly leading to system and network compromise.

Fix Text

Change the mode of the traceroute command. # chmod 0700 /usr/contrib/bin/traceroute

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

The version of the SMTP service can be used by attackers to plan an attack based on vulnerabilities present in the specific version.

Fix Text

Ensure Sendmail or its equivalent has been configured to mask the version information. If necessary, change the O SmtpGreetingMessage line in the /etc/sendmail.cf file as noted below: O SmtpGreetingMessage=$j Sendmail $v/$Z; $b change it to: O SmtpGreetingMessage= Mail Server Ready ; $b Then restart the Sendmail service.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

The .forward file allows users to automatically forward mail to another system. Use of .forward files could allow the unauthorized forwarding of mail and could potentially create mail loops which could degrade system performance.

Fix Text

Remove .forward files from the system.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

If an anonymous FTP account has been configured to use a functional shell, attackers could gain access to the shell if the account is compromised.

Fix Text

Configure anonymous FTP accounts to use a non-functional shell. If necessary, edit the /etc/passwd file to remove any functioning shells associated with the FTP account and replace them with non-functioning shells, such as /dev/null.

Check Content

Responsibility

System Administrator

IA Controls

ECCD-1, ECCD-2

Discussion

If the /etc/syslog.conf file is not owned by bin, unauthorized users could be allowed to view, edit, or delete important system messages handled by the syslog facility.

Fix Text

Use the chown command to set the owner to bin. # chown bin /etc/syslog.conf

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

If the group owner of /etc/syslog.conf is not root, bin, or sys, unauthorized users could be permitted to view, edit, or delete important system messages handled by the syslog facility.

Fix Text

Change the group owner of the /etc/syslog.conf file to root, bin, sys, or other. # chgrp root /etc/syslog.conf

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

Cron daemon control files restrict the scheduling of automated tasks and must be protected.

Fix Text

# chown root /var/adm/cron/cron.deny

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

The remshd process provides a typically unencrypted, host-authenticated remote access service. SSH should be used in place of this service.

Fix Text

Edit /etc/inetd.conf and comment out the remshd service. Refresh the inetd service. # inetd -c

Check Content

Responsibility

System Administrator

IA Controls

EBRU-1

Discussion

The rexecd process provides a typically unencrypted, host-authenticated remote access service. SSH should be used in place of this service.

Fix Text

Edit /etc/inetd.conf and comment out the line for the rexec daemon service. Restart the inetd service via the following command: # inetd -c

Check Content

Responsibility

Information Assurance Officer

Discussion

The SMTP EXPN function allows an attacker to determine if an account exists on a system, providing significant assistance to a brute force attack on user accounts. EXPN may also provide additional information concerning users on the system, such as the full names of account owners.

Fix Text

Edit the /etc/mail/sendmail.cf file and add or edit the following line: O PrivacyOptions=goaway Then restart the Sendmail service.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

The VRFY (Verify) command allows an attacker to determine if an account exists on a system, providing significant assistance to a brute force attack on user accounts. VRFY may provide additional information about users on the system, such as the full names of account owners.

Fix Text

If running Sendmail, add the line Opnovrfy to the Sendmail configuration file, usually located in /etc/mail/sendmail.cf. For other mail servers, contact the vendor for information on how to disable the verify command. Newer versions of Sendmail are available at http://www.sendmail.org or from ftp://ftp.cs.berkeley.edu/ucb/sendmail. Edit the /etc/mail/sendmail.cf file and add or edit (one of) the following line(s): O PrivacyOptions=novrfy O PrivacyOptions=goaway Then restart the Sendmail service.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

The UUCP utility is designed to assist in transferring files, executing remote commands, and sending e-mail between UNIX systems over phone lines and direct connections between systems. The UUCP utility is a primitive and arcane system with many security issues. There are alternate data transfer utilities/products that can be configured to more securely transfer data by providing for authentication as well as encryption.

Fix Text

Edit /etc/inetd.conf and comment the uucp service entry. Restart the inetd service. # inetd -c

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

The finger service provides information about the system's users to network clients. This could expose information that could be used in subsequent attacks.

Fix Text

Edit /etc/inetd.conf and comment out the fingerd line. Restart the inetd service via the following command: # inetd -c

Check Content

Responsibility

System Administrator

IA Controls

DCPP-1

Discussion

The use of longer passwords reduces the ability of attackers to successfully obtain valid passwords using guessing or exhaustive search techniques by increasing the password search space.

Fix Text

For Trusted Mode: Use the SAM/SMH interface to set the system password length attribute “MIN_PASSWORD_LENGTH” to 15 or greater. For SMSE: Note: There may be additional package/bundle updates that must be installed to support attributes in the /etc/default/security file. Install the additional LongPassword11i3 and PHI11i3 product bundles where/as required. Use the SAM/SMH interface (/etc/default/security file) and/or the userdbset command (/var/adm/userdb/* files) to update the attribute(s). See the below example(s): CRYPT_ALGORITHMS_DEPRECATE=__unix__ CRYPT_DEFAULT=6 LONG_PASSWORD=1 MIN_PASSWORD_LENGTH=15 Note: The MIN_PASSWORD_LENGTH attribute must be set equal to or greater than 15. If the "vi" editor was used to update the /etc/default/security file, save the file before exiting the editor.

Check Content

Responsibility

System Administrator

Discussion

To enforce the use of complex passwords, minimum numbers of characters of different classes are mandated. The use of complex passwords reduces the ability of attackers to successfully obtain valid passwords using guessing or exhaustive search techniques. Complexity requirements increase the password search space by requiring users to construct passwords from a larger character set than they may otherwise use.

Fix Text

For Trusted Mode: Use the SAM/SMH interface or edit the /etc/default/security file and update the PASSWORD_MIN_UPPER_CASE_CHARS attribute. See the below example: PASSWORD_MIN_UPPER_CASE_CHARS=1 If manually editing the file, save any change(s) before exiting the editor. For SMSE: Note: There may be additional package/bundle updates that must be installed to support attributes in the /etc/default/security file. Use the SAM/SMH interface (/etc/default/security file) and/or the userdbset command (/var/adm/userdb/* files) to update the PASSWORD_MIN_UPPER_CASE_CHARS attribute. See the below example: PASSWORD_MIN_UPPER_CASE_CHARS=1 Note: Never use a text editor to modify any /var/adm/userdb database file. The database contains checksums and other binary data, and editors (vi included) do not follow the file locking conventions that are used to control access to the database. If manually editing the /etc/default/security file, save any change(s) before exiting the editor.

Check Content

Responsibility

System Administrator

IA Controls

IAIA-1, IAIA-2

Discussion

To enforce the use of complex passwords, minimum numbers of characters of different classes are mandated. The use of complex passwords reduces the ability of attackers to successfully obtain valid passwords using guessing or exhaustive search techniques. Complexity requirements increase the password search space by requiring users to construct passwords from a larger character set than they may otherwise use.

Fix Text

For Trusted Mode: Use the SAM/SMH interface or edit the /etc/default/security file and update the PASSWORD_MIN_DIGIT_CHARS attribute. See the below example: PASSWORD_MIN_DIGIT_CHARS=1 If manually editing the file, save any change(s) before exiting the editor. For SMSE: Note: There may be additional package/bundle updates that must be installed to support attributes in the /etc/default/security file. Use the SAM/SMH interface (/etc/default/security file) and/or the userdbset command (/var/adm/userdb/* files) to update the PASSWORD_MIN_DIGIT_CHARS attribute. See the below example: PASSWORD_MIN_DIGIT_CHARS=1 Note: Never use a text editor to modify any /var/adm/userdb database file. The database contains checksums and other binary data, and editors (vi included) do not follow the file locking conventions that are used to control access to the database. If manually editing the /etc/default/security file, save any change(s) before exiting the editor.

Check Content

Responsibility

System Administrator

IA Controls

IAIA-1, IAIA-2

Discussion

To enforce the use of complex passwords, minimum numbers of characters of different classes are mandated. The use of complex passwords reduces the ability of attackers to successfully obtain valid passwords using guessing or exhaustive search techniques. Complexity requirements increase the password search space by requiring users to construct passwords from a larger character set than they may otherwise use.

Fix Text

For Trusted Mode: Use the SAM/SMH interface or edit the /etc/default/security file and update the PASSWORD_MIN_SPECIAL_CHARS attribute. See the below example: PASSWORD_MIN_SPECIAL_CHARS=1 If manually editing the file, save any change(s) before exiting the editor. For SMSE: Note: There may be additional package/bundle updates that must be installed to support attributes in the /etc/default/security file. Use the SAM/SMH interface (/etc/default/security file) and/or the userdbset command (/var/adm/userdb/* files) to update the PASSWORD_MIN_SPECIAL_CHARS attribute. See the below example: PASSWORD_MIN_SPECIAL_CHARS=1 Note: Never use a text editor to modify any /var/adm/userdb database file. The database contains checksums and other binary data, and editors (vi included) do not follow the file locking conventions that are used to control access to the database. If manually editing the /etc/default/security file, save any change(s) before exiting the editor.

Check Content

Responsibility

System Administrator

IA Controls

IAIA-1, IAIA-2

Discussion

Global initialization files are used to configure the user's shell environment upon login. Malicious modification of these files could compromise accounts upon logon.

Fix Text

Change the mode of the global initialization file(s) to 0444. # chmod 0444 <global initialization file>

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

Global initialization files are used to configure the user's shell environment upon login. Malicious modification of these files could compromise accounts upon logon. Failure to give ownership of sensitive files or utilities to bin provides the designated owner and unauthorized users with the potential to access sensitive information or change the system configuration which could weaken the system's security posture.

Fix Text

Change the ownership of global initialization files with incorrect ownership. # chown bin <global initialization files>

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

Global initialization files are used to configure the user's shell environment upon login. Malicious modification of these files could compromise accounts upon logon. Failure to give ownership of sensitive files or utilities to root or bin provides the designated owner and unauthorized users with the potential to access sensitive information or change the system configuration which could weaken the system's security posture.

Fix Text

Change the group ownership of the global initialization file(s) with incorrect group ownership. # chgrp root <global initialization file>

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

If the skeleton files are not protected, unauthorized personnel could change user startup parameters and possibly jeopardize user files. Failure to give ownership of sensitive files or utilities to bin provides the designated owner and unauthorized users with the potential to access sensitive information or change the system configuration which could weaken the system's security posture.

Fix Text

Change the ownership of skeleton files with incorrect mode. # chown bin <skeleton file>

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

The executable search path (typically the PATH environment variable) contains a list of directories for the shell to search to find executables. If this path includes the current working directory or other relative paths, executables in these directories may be executed instead of system commands. This variable is formatted as a colon-separated list of directories. If there is an empty entry, such as a leading or trailing colon, two consecutive colons, or a single period, this is interpreted as the current working directory. Paths starting with a slash (/) are absolute paths.

Fix Text

Edit the global initialization file(s) with PATH variables containing relative paths and remove any relative path form the PATH variables that have not been documented with the ISSO. Edit the global initialization file(s) and remove any empty entry that is defined.

Check Content

Responsibility

System Administrator

Discussion

The executable search path (typically the PATH environment variable) contains a list of directories for the shell to search to find executables. If this path includes the current working directory or other relative paths, executables in these directories may be executed instead of system commands. This variable is formatted as a colon-separated list of directories. If there is an empty entry, such as a leading or trailing colon, two consecutive colons, or a single period, this is interpreted as the current working directory. Paths starting with a slash (/) are absolute paths.

Fix Text

Edit the local initialization file and remove the relative path entries from the PATH variable that have not been documented with the ISSO. Edit the local initialization file and remove any empty entry that is defined.

Check Content

Responsibility

System Administrator

Discussion

The .rhosts, .shosts, hosts.equiv, and shosts.equiv files are used to configure host-based authentication for individual users or the system. Host-based authentication is not sufficient for preventing unauthorized access to the system.

Fix Text

Remove the .rhosts, .shosts, hosts.equiv, and/or shosts.equiv files.

Check Content

Responsibility

Information Assurance Officer

IA Controls

ECCD-1, ECCD-2

Discussion

.rhosts files are used to specify a list of hosts permitted remote access to a particular account without authenticating. The use of such a mechanism defeats strong identification and authentication requirements.

Fix Text

Edit /etc/pam.conf and comment/remove the "rcomds" line(s).

Check Content

Responsibility

Information Assurance Officer

Discussion

To centralize the management of privileged account crontabs, of the default system accounts, only root may have a crontab.

Fix Text

Remove default system accounts (such as bin, sys, adm, or others) from the cron.allow file if it exists, or add those accounts to the cron.deny file.

Check Content

Responsibility

System Administrator

IA Controls

ECPA-1

Discussion

Process core dumps contain the memory in use by the process when it crashed. Process core dump files can be of significant size and their use can result in file systems filling to capacity, which may result in Denial of Service. Process core dumps can be useful for software debugging.

Fix Text

Edit /etc/profile, ensure the ulimit command is present with the -c argument of the ulimit command set to 0.

Check Content

Responsibility

System Administrator

IA Controls

ECCD-1, ECCD-2

Discussion

A common type of exploit is the stack buffer overflow. An application receives, from an attacker, more data than it is prepared for and stores this information on its stack, writing beyond the space reserved for it. This can be designed to cause execution of the data written on the stack. One mechanism to mitigate this vulnerability is for the system to not allow the execution of instructions in sections of memory identified as part of the stack.

Fix Text

# kctune executable_stack=0 The system will require a restart/reboot for the setting to take effect.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

Source-routed packets allow the source of the packet to suggest routers forward the packet along a different path than configured on the router, which can be used to bypass network security measures. This requirement applies only to the forwarding of source-routed traffic, such as when IPv4 forwarding is enabled and the system is functioning as a router.

Fix Text

Disable the IP source-routed forwarding feature. # ndd -set /dev/ip ip_forward_src_routed 0 Edit /etc/rc.config.d/nddconf and add/set: TRANSPORT_NAME[x] = ip NDD_NAME[x] = ip_forward_src_routed NDD_VALUE[x] = 0

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

The use of separate file systems for different paths can protect the system from failures resulting from the / file system becoming full or failing.

Fix Text

Migrate the /home (or equivalent) path onto a separate file system.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

Unnecessary services should be disabled to decrease the attack surface of the system.

Fix Text

Remove or disable the inetd startup scripts and kill the service.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

The HELP command should be disabled to mask version information. The version of the SMTP service software could be used by attackers to target vulnerabilities present in specific software versions.

Fix Text

To disable the SMTP HELP command, remove or empty the Sendmail help file: /etc/mail/helpfile.

Check Content

Responsibility

System Administrator

Discussion

The umask controls the default access mode assigned to newly created files. An umask of 077 limits new files to mode 700 or less permissive. Although umask is stored as a 4-digit number, the first digit representing special access modes is typically ignored or required to be zero.

Fix Text

Edit the initialization files for the ftp user and set the umask to 077.

Check Content

Responsibility

System Administrator

IA Controls

ECCD-1, ECCD-2

Discussion

.Xauthority files ensure the user is authorized to access the specific X Windows host. Excessive permissions may permit unauthorized modification of these files, which could lead to Denial of Service to authorized access or allow unauthorized access to be obtained.

Fix Text

Change the mode of the .Xauthority files. # chmod 0600 .Xauthority

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

The snmpd.conf file contains authenticators and must be protected from unauthorized access and modification. If the file is not owned by bin, it may be subject to access and modification from unauthorized users.

Fix Text

Change the owner of the snmpd.conf file to bin. # chown bin /etc/SnmpAgent.d/snmpd.conf

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

Unintentionally running a syslog server accepting remote messages puts the system at increased risk. Malicious syslog messages sent to the server could exploit vulnerabilities in the server software itself, could introduce misleading information in to the system's logs, or could fill the system's storage leading to a Denial of Service.

Fix Text

Edit the /etc/rc.config.d/syslogd configuration startup script and add the -N option to the syslogd command. Restart the syslogd service via the following command(s): # /sbin/init.d/syslogd stop # /sbin/init.d/syslogd start

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

The SSH daemon must be configured for IP filtering to provide a layered defense against connection attempts from unauthorized addresses.

Fix Text

Add appropriate IP restrictions for SSH to the /etc/hosts.deny and/or /etc/hosts.allow files.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

If the system is configured for IP forwarding and is not a designated router, it could be used to bypass network security by providing a path for communication not filtered by network devices.

Fix Text

Edit /etc/rc.config.d/nddconf and set the ip_forwarding option to 0.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

If the system's access control program is not configured with appropriate rules for allowing and denying access to system network resources, services may be accessible to unauthorized hosts.

Fix Text

Edit the <path>/hosts.allow and <path/hosts.deny files to configure access restrictions.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

Network analysis tools allow for the capture of network traffic visible to the system.

Fix Text

Remove the network analysis tool binary from the system. Consult vendor documentation for removing packaged software, or remove the binary directly via the following example: # rm -i <binary>

Check Content

Responsibility

System Administrator

IA Controls

DCPA-1

Discussion

A synchronized system clock is critical for the enforcement of time-based policies and the correlation of logs and audit records with other systems. If an illicit time source is used for synchronization, the integrity of system logs and the security of the system could be compromised. If the configuration files controlling time synchronization are not owned by a system account, unauthorized modifications could result in the failure of time synchronization.

Fix Text

Change the owner of the NTP configuration file. # chown root /etc/ntp.conf

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

A synchronized system clock is critical for the enforcement of time-based policies and the correlation of logs and audit records with other systems. If an illicit time source is used for synchronization, the integrity of system logs and the security of the system could be compromised. If the configuration files controlling time synchronization are not owned by a system group, unauthorized modifications could result in the failure of time synchronization.

Fix Text

Change the group-owner of the NTP configuration file. Procedure: # chgrp root /etc/ntp.conf

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

A synchronized system clock is critical for the enforcement of time-based policies and the correlation of logs and audit records with other systems. If an illicit time source is used for synchronization, the integrity of system logs and the security of the system could be compromised. If the configuration files controlling time synchronization are not protected, unauthorized modifications could result in the failure of time synchronization.

Fix Text

Change the mode of the NTP configuration file to 0640 or less permissive. # chmod 0640 /etc/ntp.conf

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1

Discussion

Limiting simultaneous user logins can insulate the system from Denial of Service problems caused by excessive logins. Automated login processes operating improperly or maliciously may result in an exceptional number of simultaneous login sessions. If the defined value of 10 logins does not meet operational requirements, the site may define the permitted number of simultaneous login sessions based on operational requirements. This limit is for the number of simultaneous login sessions for EACH user account. This is NOT a limit on the total number of simultaneous login sessions on the system.

Fix Text

For Trusted Mode: Use the SAM/SMH interface (/etc/default/security file) to update attribute. See the below example: NUMBER_OF_LOGINS_ALLOWED=10 For SMSE: Note: There may be additional package/bundle updates that must be installed to support attributes in the /etc/default/security file. Use the SAM/SMH interface (/etc/default/security file) and/or the userdbset command (/var/adm/userdb/* files) to update attribute. See the below example: NUMBER_OF_LOGINS_ALLOWED=10 Note: Never use a text editor to modify any /var/adm/userdb database file. The database contains checksums and other binary data, and editors (vi included) do not follow the file locking conventions that are used to control access to the database. If manually editing the /etc/default/security file, save any change(s) before exiting the editor.

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

Providing users with feedback on when account accesses last occurred facilitates user recognition and reporting of unauthorized account use.

Fix Text

Edit the configuration file and modify the PrintLastLog line entry as follows: PrintLastLog yes

Check Content

Responsibility

System Administrator

IA Controls

ECSC-1

Discussion

To enforce the use of complex passwords, minimum numbers of characters of different classes are mandated. The use of complex passwords reduces the ability of attackers to successfully obtain valid passwords using guessing or exhaustive search techniques. Complexity requirements increase the password search space by requiring users to construct passwords from a larger character set than they may otherwise use.

Fix Text

For Trusted Mode: Use the SAM/SMH interface or edit the /etc/default/security file and update the PASSWORD_MIN_LOWER_CASE_CHARS attribute. See the below example: PASSWORD_MIN_LOWER_CASE_CHARS=1 If manually editing the file, save any change(s) before exiting the editor. For SMSE: Note: There may be additional package/bundle updates that must be installed to support attributes in the /etc/default/security file. Use the SAM/SMH interface (/etc/default/security file) and/or the userdbset command (/var/adm/userdb/* files) to update the PASSWORD_MIN_LOWER_CASE_CHARS attribute. See the below example: PASSWORD_MIN_LOWER_CASE_CHARS=1 Note: Never use a text editor to modify any /var/adm/userdb database file. The database contains checksums and other binary data, and editors (vi included) do not follow the file locking conventions that are used to control access to the database. If manually editing the /etc/default/security file, save any change(s) before exiting the editor.

Check Content

Responsibility

System Administrator

IA Controls

IAIA-1, IAIA-2

Discussion

Configuring a supplemental group for users permitted to switch to the root user prevents unauthorized users from accessing the root account, even with knowledge of the root credentials.

Fix Text

Edit /etc/default/security and uncomment, set, or add the SU_ROOT_GROUP setting with a value of wheel or equivalent. If necessary, create a wheel group and add administrative users to the group.

Check Content

Responsibility

System Administrator

IA Controls

ECLP-1