Apache Server 2.4 UNIX Site Security Technical Implementation Guide
| Version 1 Release 0.1 |
| 2018-12-07 |
| U_Apache_Server_2-4_UNIX_Site_STIG_V1R0-1_Manual-xccdf.xml |
| This Security Technical Implementation Guide is published as a tool to improve the security of Department of Defense (DoD) information systems. The requirements are derived from the National Institute of Standards and Technology (NIST) 800-53 and related documents. Comments or proposed revisions to this document should be sent via email to the following address: disa.stig_spt@mail.mil. |
Vulnerabilities (44)
The Apache web server must set an inactive timeout for sessions.
Discussion
Leaving sessions open indefinitely is a major security risk. An attacker can easily use an already authenticated session to access the hosted application as the previously authenticated user. By closing sessions after a set period of inactivity, the Apache web server can make certain that those sessions that are not closed through the user logging out of an application are eventually closed. Acceptable values are 5 minutes for high-value applications, 10 minutes for medium-value applications, and 20 minutes for low-value applications.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Load the "Reqtimeout_module". Set the "RequestReadTimeout" directive.
Check Content
In a command line, run "httpd -M | grep -i Reqtimeout_module". If the "Reqtimeout_module" is not enabled, this is a finding.
The Apache web server must produce log records that contain sufficient information to establish the outcome (success or failure) of events.
Discussion
Apache web server logging capability is critical for accurate forensic analysis. Without sufficient and accurate information, a correct replay of the events cannot be determined. Ascertaining the correct source of the events (e.g., source IP) is important during forensic analysis. Correctly determining the source of events will add information to the overall reconstruction of the logable event. By determining the source of the event correctly, analysis of the enterprise can be undertaken to determine if events tied to the source occurred in other areas within the enterprise. A web server behind a load balancer or proxy server, when not configured correctly, will record the load balancer or proxy server as the source of every logable event. When looking at the information forensically, this information is not helpful in the investigation of events. The web server must record with each event the client source of the event.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Ensure the "SSLProtocol" is added and looks like the following: SSLProtocol -ALL +TLSv1.2 Restart Apache: apachectl restart
Check Content
In a command line, run "httpd -M | grep -i ssl_module". If the "ssl_module" is not enabled, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Search for the directive "SSLProtocol" in the "httpd.conf" file: # cat /<path_to_file>/httpd.conf | grep -i "SSLProtocol" If the "SSLProtocol" directive is missing or does not look like the following, this is a finding: SSLProtocol -ALL +TLSv1.2 If the TLS version is not TLS 1.2 or higher, according to NIST SP 800-52 Rev 2, or if non-FIPS-approved algorithms are enabled, this is a finding. NOTE: In some cases, web servers are configured in an environment to support load balancing. This configuration most likely uses a content switch to control traffic to the various web servers. In this situation, the TLS certificate for the websites may be installed on the content switch versus the individual websites. This solution is acceptable as long as the web servers are isolated from the general population LAN. Users should not have the ability to bypass the content switch to access the websites.
The Apache web server must perform server-side session management.
Discussion
Session management is the practice of protecting the bulk of the user authorization and identity information. This data can be stored on the client system or on the server. When the session information is stored on the client, the session ID, along with the user authorization and identity information, is sent along with each client request and is stored in a cookie, embedded in the uniform resource locator (URL), or placed in a hidden field on the displayed form. Each of these offers advantages and disadvantages. The biggest disadvantage to all three is the possibility of the hijacking of a session along with all of the user's credentials. When the user authorization and identity information is stored on the server in a protected and encrypted database, the communication between the client and Apache web server will only send the session identifier, and the server can then retrieve user credentials for the session when needed. If, during transmission, the session were to be hijacked, the user's credentials would not be compromised.
Fix Text
If the modules are not installed, install any missing packages. Add the following lines to the "httpd.conf" file: LoadModule usertrack_module modules/mod_usertrack.so LoadModule session_module modules/mod_session.so Additional documentation can be found at: https://httpd.apache.org/docs/2.4/mod/mod_usertrack.html https://httpd.apache.org/docs/2.4/mod/mod_session.html Restart Apache: apachectl restart
Check Content
In a command line, run "httpd -M | grep -i mod_session" and "httpd -M | grep -i mod_usertrack". If "mod_session" module and "mod_usertrack" are not enabled or do not exist, this is a finding.
The Apache web server must use encryption strength in accordance with the categorization of data hosted by the Apache web server when remote connections are provided.
Discussion
The Apache web server has several remote communications channels. Examples are user requests via http/https, communication to a backend database, and communication to authenticate users. The encryption used to communicate must match the data that is being retrieved or presented. Methods of communication are "http" for publicly displayed information, "https" to encrypt when user data is being transmitted, VPN tunneling, or other encryption methods to a database.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Ensure the "SSLProtocol" is added and looks like the following: SSLProtocol -ALL +TLSv1.2 Restart Apache: apachectl restart
Check Content
In a command line, run "httpd -M | grep -i ssl_module". If the "ssl_module" is not enabled, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Search for the directive "SSLProtocol" in the "httpd.conf" file: # cat /<path_to_file>/httpd.conf | grep -i "SSLProtocol" If the "SSLProtocol" directive is missing or does not look like the following, this is a finding: SSLProtocol -ALL +TLSv1.2 If the TLS version is not TLS 1.2 or higher, according to NIST SP 800-52 Rev 2, or if non-FIPS-approved algorithms are enabled, this is a finding. NOTE: In some cases, web servers are configured in an environment to support load balancing. This configuration most likely uses a content switch to control traffic to the various web servers. In this situation, the TLS certificate for the websites may be installed on the content switch versus the individual websites. This solution is acceptable as long as the web servers are isolated from the general population LAN. Users should not have the ability to bypass the content switch to access the websites.
The Apache web server must use cryptography to protect the integrity of remote sessions.
Discussion
Data exchanged between the user and the Apache web server can range from static display data to credentials used to log on to the hosted application. Even when data appears to be static, the non-displayed logic in a web page may expose business logic or trusted system relationships. The integrity of all the data being exchanged between the user and Apache web server must always be trusted. To protect the integrity and trust, encryption methods should be used to protect the complete communication session.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Ensure the "SSLProtocol" is added and looks like the following: SSLProtocol -ALL +TLSv1.2 Restart Apache: apachectl restart
Check Content
In a command line, run "httpd -M | grep -i ssl_module". If the "ssl_module" is not enabled, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Search for the directive "SSLProtocol" in the "httpd.conf" file: # cat /<path_to_file>/httpd.conf | grep -i "SSLProtocol" If the "SSLProtocol" directive is missing or does not look like the following, this is a finding: SSLProtocol -ALL +TLSv1.2 If the TLS version is not TLS 1.2 or higher, according to NIST SP 800-52 Rev 2, or if non-FIPS-approved algorithms are enabled, this is a finding. NOTE: In some cases, web servers are configured in an environment to support load balancing. This configuration most likely uses a content switch to control traffic to the various web servers. In this situation, the TLS certificate for the websites may be installed on the content switch versus the individual websites. This solution is acceptable as long as the web servers are isolated from the general population LAN. Users should not have the ability to bypass the content switch to access the websites.
The Apache web server must enforce approved authorizations for logical access to hosted applications and resources in accordance with applicable access control policies.
Discussion
To control access to sensitive information and hosted applications by entities that have been issued certificates by DoD-approved PKIs, the Apache web server must be properly configured to incorporate a means of authorization that does not simply rely on the possession of a valid certificate for access. Access decisions must include a verification that the authenticated entity is permitted to access the information or application. Authorization decisions must leverage a variety of methods, such as mapping the validated PKI certificate to an account with an associated set of permissions on the system. If the Apache web server relied only on the possession of the certificate and did not map to system roles and privileges, each user would have the same abilities and roles to make changes to the production system.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Ensure the "SSLProtocol" is added and looks like the following: SSLProtocol -ALL +TLSv1.2 Restart Apache: apachectl restart
Check Content
In a command line, run "httpd -M | grep -i ssl_module". If the "ssl_module" is not enabled, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Search for the directive "SSLProtocol" in the "httpd.conf" file: # cat /<path_to_file>/httpd.conf | grep -i "SSLProtocol" If the "SSLProtocol" directive is missing or does not look like the following, this is a finding: SSLProtocol -ALL +TLSv1.2 If the TLS version is not TLS 1.2 or higher, according to NIST SP 800-52 Rev 2, or if non-FIPS-approved algorithms are enabled, this is a finding. NOTE: In some cases, web servers are configured in an environment to support load balancing. This configuration most likely uses a content switch to control traffic to the various web servers. In this situation, the TLS certificate for the websites may be installed on the content switch versus the individual websites. This solution is acceptable as long as the web servers are isolated from the general population LAN. Users should not have the ability to bypass the content switch to access the websites.
The Apache web server must produce log records containing sufficient information to establish what type of events occurred.
Discussion
Apache web server logging capability is critical for accurate forensic analysis. Without sufficient and accurate information, a correct replay of the events cannot be determined. Ascertaining the correct type of event that occurred is important during forensic analysis. The correct determination of the event and when it occurred is important in relation to other events that happened at that same time. Without sufficient information establishing what type of log event occurred, investigation into the cause of event is severely hindered. Log record content that may be necessary to satisfy the requirement of this control includes but is not limited to time stamps, source and destination IP addresses, user/process identifiers, event descriptions, application-specific events, success/fail indications, file names involved, access control, and flow control rules invoked.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Uncomment the "log_config_module" module line. Configure the "LogFormat" in the "httpd.conf" file to look like the following: LogFormat "%a %A %h %H %l %m %s %t %u %U \"%{Referer}i\" " combined Restart Apache: apachectl restart
Check Content
In a command line, run "httpd -M | grep -i log_config_module". If the "log_config_module" is not enabled, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Search for the directive "LogFormat" in the httpd.conf file: # cat /<path_to_file>/httpd.conf | grep -i "LogFormat" If the "LogFormat" directive is missing or does not look like the following, this is a finding: LogFormat "%a %A %h %H %l %m %s %t %u %U \"%{Referer}i\
The Apache web server must produce log records containing sufficient information to establish the identity of any user/subject or process associated with an event.
Discussion
Apache web server logging capability is critical for accurate forensic analysis. Without sufficient and accurate information, a correct replay of the events cannot be determined. Ascertaining the success or failure of an event is important during forensic analysis. Correctly determining the outcome will add information to the overall reconstruction of the logable event. By determining the success or failure of the event correctly, analysis of the enterprise can be undertaken to determine if events tied to the event occurred in other areas within the enterprise. Without sufficient information establishing the success or failure of the logged event, investigation into the cause of event is severely hindered. The success or failure also provides a means to measure the impact of an event and help authorized personnel to determine the appropriate response. Log record content that may be necessary to satisfy the requirement of this control includes but is not limited to time stamps, source and destination IP addresses, user/process identifiers, event descriptions, application-specific events, success/fail indications, file names involved, access control, and flow control rules invoked.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Ensure the "SSLProtocol" is added and looks like the following: SSLProtocol -ALL +TLSv1.2 Restart Apache: apachectl restart
Check Content
In a command line, run "httpd -M | grep -i ssl_module". If the "ssl_module" is not enabled, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Search for the directive "SSLProtocol" in the "httpd.conf" file: # cat /<path_to_file>/httpd.conf | grep -i "SSLProtocol" If the "SSLProtocol" directive is missing or does not look like the following, this is a finding: SSLProtocol -ALL +TLSv1.2 If the TLS version is not TLS 1.2 or higher, according to NIST SP 800-52 Rev 2, or if non-FIPS-approved algorithms are enabled, this is a finding. NOTE: In some cases, web servers are configured in an environment to support load balancing. This configuration most likely uses a content switch to control traffic to the various web servers. In this situation, the TLS certificate for the websites may be installed on the content switch versus the individual websites. This solution is acceptable as long as the web servers are isolated from the general population LAN. Users should not have the ability to bypass the content switch to access the websites.
The Apache web server must not perform user management for hosted applications.
Discussion
User management and authentication can be an essential part of any application hosted by the web server. Along with authenticating users, the user management function must perform several other tasks such as password complexity, locking users after a configurable number of failed logons, and management of temporary and emergency accounts. All of this must be done enterprise-wide. The web server contains a minimal user management function, but the web server user management function does not offer enterprise-wide user management, and user management is not the primary function of the web server. User management for the hosted applications should be done through a facility that is built for enterprise-wide user management, like LDAP and Active Directory.
Fix Text
Reconfigure any hosted applications on the Apache web server to perform user management outside the web server. Document how the hosted application user management is accomplished.
Check Content
Interview the System Administrator (SA) about the role of the Apache web server. If the web server is hosting an application, have the SA provide supporting documentation on how the application's user management is accomplished outside of the web server. If the web server is not hosting an application, this is Not Applicable. If the web server is performing user management for hosted applications, this is a finding. If the web server is hosting an application and the SA cannot provide supporting documentation on how the application's user management is accomplished outside of the Apache web server, this is a finding.
The Apache web server must have Multipurpose Internet Mail Extensions (MIME) that invoke operating system shell programs disabled.
Discussion
Controlling what a user of a hosted application can access is part of the security posture of the web server. Any time a user can access more functionality than is needed for the operation of the hosted application poses a security issue. A user with too much access can view information that is not needed for the user's job role, or the user could use the function in an unintentional manner. A MIME tells the web server what type of program various file types and extensions are and what external utilities or programs are needed to execute the file type. A shell is a program that serves as the basic interface between the user and the operating system, so hosted application users must not have access to these programs. Shell programs may execute shell escapes and can then perform unauthorized activities that could damage the security posture of the web server.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Disable MIME types for .exe, .dll, .com, .bat, and .csh programs. If "Action" or "AddHandler" exist and they configure any of the following (.exe, .dll, .com, .bat, or .csh), remove those references. Restart Apache: apachectl restart Ensure this process is documented and approved by the ISSO.
Check Content
In a command line, run "httpd -M | grep -i ssl_module". If the "ssl_module" is not enabled, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" If "Action" or "AddHandler" exist and they configure .exe, .dll, .com, .bat, or .csh, or any other shell as a viewer for documents, this is a finding. If this is not documented and approved by the Information System Security Officer (ISSO), this is a finding.
The Apache web server must allow mappings to unused and vulnerable scripts to be removed.
Discussion
Scripts allow server-side processing on behalf of the hosted application user or as processes needed in the implementation of hosted applications. Removing scripts not needed for application operation or deemed vulnerable helps to secure the web server. To ensure scripts are not added to the web server and run maliciously, script mappings that are not needed or used by the web server for hosted application operation must be removed.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Remove any scripts in "cgi-bin" directory if they are not needed for application operation. Ensure this process is documented and approved by the ISSO.
Check Content
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Review "Script", "ScriptAlias" or "ScriptAliasMatch", or "ScriptInterpreterSource" directives. Go into each directory and locate "cgi-bin" files. If any scripts are present that are not needed for application operation, this is a finding. If this is not documented and approved by the Information System Security Officer (ISSO), this is a finding.
The Apache web server must have resource mappings set to disable the serving of certain file types.
Discussion
Resource mapping is the process of tying a particular file type to a process in the web server that can serve that type of file to a requesting client and to identify which file types are not to be delivered to a client. By not specifying which files can and cannot be served to a user, the web server could deliver to a user web server configuration files, log files, password files, etc. The web server must only allow hosted application file types to be served to a user, and all other types must be disabled.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Disable MIME types for .exe, .dll, .com, .bat, and .csh programs. If "Action" or "AddHandler" exist and they configure .exe, .dll, .com, .bat, or .csh, remove those references. Restart Apache: apachectl restart Ensure this process is documented and approved by the ISSO.
Check Content
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" If "Action" or "AddHandler" exist and they configure .exe, .dll, .com, .bat, or .csh, or any other shell as a viewer for documents, this is a finding. If this is not documented and approved by the Information System Security Officer (ISSO), this is a finding.
Users and scripts running on behalf of users must be contained to the document root or home directory tree of the Apache web server.
Discussion
A web server is designed to deliver content and execute scripts or applications on the request of a client or user. Containing user requests to files in the directory tree of the hosted web application and limiting the execution of scripts and applications guarantees that the user is not accessing information protected outside the application's realm. The web server must also prohibit users from jumping outside the hosted application directory tree through access to the user's home directory, symbolic links or shortcuts, or through search paths for missing files.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Set the root directory directive as follows: <Directory> ... Require all denied ... </Directory> Remove any "Deny" and "Allow" directives from the root <Directory> element. Restart Apache: apachectl restart
Check Content
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Verify there is a single "Require" directive with the value of "all denied". Verify there are no "Allow" or "Deny" directives in the root <Directory> element. The following may be useful in extracting root directory elements from the Apache configuration for auditing: # perl -ne 'print if /^ *<Directory *\//i .. /<\/Directory/i' $APACHE_PREFIX/conf/httpd.conf If there are "Allow" or "Deny" directives in the root <Directory> element, this is a finding.
The Apache web server must be configured to use a specified IP address and port.
Discussion
The web server must be configured to listen on a specified IP address and port. Without specifying an IP address and port for the web server to use, the web server will listen on all IP addresses available to the hosting server. If the web server has multiple IP addresses, i.e., a management IP address, the web server will also accept connections on the management IP address. Accessing the hosted application through an IP address normally used for non-application functions opens the possibility of user access to resources, utilities, files, ports, and protocols that are protected on the desired application IP address.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Set each "VirtualHost" directive to listen to on a specific IP address and port.
Check Content
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Verify that for each "VirtualHost" directive, there is an IP address and port. If there is not, this is a finding.
The Apache web server must encrypt passwords during transmission.
Discussion
Data used to authenticate, especially passwords, needs to be protected at all times, and encryption is the standard method for protecting authentication data during transmission. Data used to authenticate can be passed to and from the web server for many reasons. Examples include data passed from a user to the web server through an HTTPS connection for authentication, the web server authenticating to a backend database for data retrieval and posting, and the web server authenticating to a clustered web server manager for an update.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Ensure the "SSLProtocol" is added and looks like the following: SSLProtocol -ALL +TLSv1.2 Restart Apache: apachectl restart
Check Content
In a command line, run "httpd -M | grep -i ssl_module". If the "ssl_module" is not enabled, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Search for the directive "SSLProtocol" in the "httpd.conf" file: # cat /<path_to_file>/httpd.conf | grep -i "SSLProtocol" If the "SSLProtocol" directive is missing or does not look like the following, this is a finding: SSLProtocol -ALL +TLSv1.2 If the TLS version is not TLS 1.2 or higher, according to NIST SP 800-52 Rev 2, or if non-FIPS-approved algorithms are enabled, this is a finding. NOTE: In some cases, web servers are configured in an environment to support load balancing. This configuration most likely uses a content switch to control traffic to the various web servers. In this situation, the TLS certificate for the websites may be installed on the content switch versus the individual websites. This solution is acceptable as long as the web servers are isolated from the general population LAN. Users should not have the ability to bypass the content switch to access the websites.
The Apache web server must perform RFC 5280-compliant certification path validation.
Discussion
A certificate's certification path is the path from the end entity certificate to a trusted root certification authority (CA). Certification path validation is necessary for a relying party to make an informed decision regarding acceptance of an end entity certificate. Certification path validation includes checks such as certificate issuer trust, time validity, and revocation status for each certificate in the certification path. Revocation status information for CA and subject certificates in a certification path is commonly provided via certificate revocation lists (CRLs) or online certificate status protocol (OCSP) responses.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "ssl.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" Edit <'HTTPD_ROOT'>/conf.d/ssl.conf Set "SSLVerifyClient" to "require". Set "SSLVerifyDepth" to "1". SSLVerifyDepth 1 For more information: https://httpd.apache.org/docs/current/mod/ssl_module.html
Check Content
In a command line, run "httpd -M | grep -i ssl_module". If the "ssl_module" is not enabled, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "ssl.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" Review <'HTTPD_ROOT'>/conf.d/ssl.conf Verify "SSLVerifyClient" is set to "require": SSLVerifyClient require Verify "SSLVerifyDepth" is set to a number greater than "0": SSLVerifyDepth 1 If "SSLVerifyClient" is not set to "require" or "SSLVerifyDepth" is not set to a number greater than "0", this is a finding.
Only authenticated system administrators or the designated PKI Sponsor for the Apache web server must have access to the Apache web servers private key.
Discussion
The web server's private key is used to prove the identity of the server to clients and securely exchange the shared secret key used to encrypt communications between the web server and clients. By gaining access to the private key, an attacker can pretend to be an authorized server and decrypt the SSL traffic between a client and the web server.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Based on the "SSLCertificateFile" directive path, configure the Apache web server to ensure only authenticated and authorized users can access the web server's private key.
Check Content
In a command line, run "httpd -M | grep -i ssl_module". If the "ssl_module" is not enabled, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Review the private key path in the "SSLCertificateFile" directive. Verify only authenticated system administrators and the designated PKI Sponsor for the web server can access the web server private key. If the private key is accessible by unauthenticated or unauthorized users, this is a finding.
The Apache web server must use cryptographic modules that meet the requirements of applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance when encrypting stored data.
Discussion
Encryption is only as good as the encryption modules used. Unapproved cryptographic module algorithms cannot be verified and cannot be relied upon to provide confidentiality or integrity, and DoD data may be compromised due to weak algorithms. FIPS 140-2 is the current standard for validating cryptographic modules and NSA Type-X (where X=1, 2, 3, 4) products are NSA-certified, hardware-based encryption modules. The web server must provide FIPS-compliant encryption modules when storing encrypted data and configuration settings.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Ensure the "SSLProtocol" is added and looks like the following: SSLProtocol -ALL +TLSv1.2 Restart Apache: apachectl restart
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In a command line, run "httpd -M | grep -i ssl_module". If the "ssl_module" is not enabled, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Search for the directive "SSLProtocol" in the "httpd.conf" file: # cat /<path_to_file>/httpd.conf | grep -i "SSLProtocol" If the "SSLProtocol" directive is missing or does not look like the following, this is a finding: SSLProtocol -ALL +TLSv1.2 If the TLS version is not TLS 1.2 or higher, according to NIST SP 800-52 Rev 2, or if non-FIPS-approved algorithms are enabled, this is a finding. NOTE: In some cases, web servers are configured in an environment to support load balancing. This configuration most likely uses a content switch to control traffic to the various web servers. In this situation, the TLS certificate for the websites may be installed on the content switch versus the individual websites. This solution is acceptable as long as the web servers are isolated from the general population LAN. Users should not have the ability to bypass the content switch to access the websites.
The Apache web server must use cryptographic modules that meet the requirements of applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance for such authentication.
Discussion
Encryption is only as good as the encryption modules used. Unapproved cryptographic module algorithms cannot be verified and cannot be relied upon to provide confidentiality or integrity, and DoD data may be compromised due to weak algorithms. FIPS 140-2 is the current standard for validating cryptographic modules and NSA Type-X (where X=1, 2, 3, 4) products are NSA-certified, hardware-based encryption modules. The Apache web server must provide FIPS-compliant encryption modules when storing encrypted data and configuration settings.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Ensure the "SSLProtocol" is added and looks like the following: SSLProtocol -ALL +TLSv1.2 Restart Apache: apachectl restart
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In a command line, run "httpd -M | grep -i ssl_module". If the "ssl_module" is not enabled, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Search for the directive "SSLProtocol" in the "httpd.conf" file: # cat /<path_to_file>/httpd.conf | grep -i "SSLProtocol" If the "SSLProtocol" directive is missing or does not look like the following, this is a finding: SSLProtocol -ALL +TLSv1.2 If the TLS version is not TLS 1.2 or higher, according to NIST SP 800-52 Rev 2, or if non-FIPS-approved algorithms are enabled, this is a finding. NOTE: In some cases, web servers are configured in an environment to support load balancing. This configuration most likely uses a content switch to control traffic to the various web servers. In this situation, the TLS certificate for the websites may be installed on the content switch versus the individual websites. This solution is acceptable as long as the web servers are isolated from the general population LAN. Users should not have the ability to bypass the content switch to access the websites.
An Apache web server using mobile code must meet DoD-defined mobile code requirements.
Discussion
Mobile code in hosted applications allows the developer to add functionality and displays to hosted applications that are fluid, as opposed to a static web page. The data presentation becomes more appealing to the user and is easier to analyze, and navigation through the hosted application and data is much less complicated. Some mobile code technologies in use in today's applications are Java, JavaScript, ActiveX, PDF, Postscript, Shockwave movies, Flash animations, and VBScript. The DoD has created policies that define the usage of mobile code on DoD systems. The usage restrictions and implementation guidance apply to both the selection and use of mobile code installed on organizational servers and mobile code downloaded and executed on individual workstations. The web server may host applications that contain mobile code and therefore must meet the DoD-defined requirements regarding the deployment and/or use of mobile code. This includes digitally signing applets provide a means for the client to establish application authenticity.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Ensure the "SSLProtocol" is added and looks like the following: SSLProtocol -ALL +TLSv1.2 Restart Apache: apachectl restart
Check Content
In a command line, run "httpd -M | grep -i ssl_module". If the "ssl_module" is not enabled, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Search for the directive "SSLProtocol" in the "httpd.conf" file: # cat /<path_to_file>/httpd.conf | grep -i "SSLProtocol" If the "SSLProtocol" directive is missing or does not look like the following, this is a finding: SSLProtocol -ALL +TLSv1.2 If the TLS version is not TLS 1.2 or higher, according to NIST SP 800-52 Rev 2, or if non-FIPS-approved algorithms are enabled, this is a finding. NOTE: In some cases, web servers are configured in an environment to support load balancing. This configuration most likely uses a content switch to control traffic to the various web servers. In this situation, the TLS certificate for the websites may be installed on the content switch versus the individual websites. This solution is acceptable as long as the web servers are isolated from the general population LAN. Users should not have the ability to bypass the content switch to access the websites.
Cookies exchanged between the Apache web server and client, such as session cookies, must have security settings that disallow cookie access outside the originating Apache web server and hosted application.
Discussion
Cookies are used to exchange data between the web server and the client. Cookies, such as a session cookie, may contain session information and user credentials used to maintain a persistent connection between the user and the hosted application since HTTP/HTTPS is a stateless protocol. When the cookie parameters are not set properly (i.e., domain and path parameters), cookies can be shared within hosted applications residing on the same web server or to applications hosted on different web servers residing on the same domain.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Add or configure the following line: "Header always edit Set-Cookie ^(.*)$ $1;HttpOnly;secure" Add the "secure" attribute to the JavaScript set cookie in any application code: function setCookie() { document.cookie = "ALEPH_SESSION_ID = $SESS; path = /; secure"; } HttpOnly cannot be used since by definition this is a cookie set by JavaScript. Restart www_server and Apache.
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Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" If "HttpOnly" "secure" is not configured, this is a finding. "Header always edit Set-Cookie ^(.*)$ $1;HttpOnly;secure" Review the code. If, when creating cookies, the following is not occurring, this is a finding: function setCookie() { document.cookie = "ALEPH_SESSION_ID = $SESS; path = /; secure"; }
The Apache web server must augment re-creation to a stable and known baseline.
Discussion
Making certain that the web server has not been updated by an unauthorized user is always a concern. Adding patches, functions, and modules that are untested and not part of the baseline opens the possibility for security risks. The web server must offer, and not hinder, a method that allows for the quick and easy reinstallation of a verified and patched baseline to guarantee the production web server is up-to-date and has not been modified to add functionality or expose security risks. When the web server does not offer a method to roll back to a clean baseline, external methods, such as a baseline snapshot or virtualizing the web server, can be used.
Fix Text
Prepare documentation for disaster recovery methods for the Apache web server in the event of the necessity for rollback. Document and test the disaster recovery methods designed.
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Interview the System Administrator for the Apache web server. Ask for documentation on the disaster recovery methods tested and planned for the Apache web server in the event of the necessity for rollback. If documentation for a disaster recovery has not been established, this is a finding.
The Apache web server document directory must be in a separate partition from the Apache web servers system files.
Discussion
A web server is used to deliver content on the request of a client. The content delivered to a client must be controlled, allowing only hosted application files to be accessed and delivered. To allow a client access to system files of any type is a major security risk that is entirely avoidable. Obtaining such access is the goal of directory traversal and URL manipulation vulnerabilities. To facilitate such access by misconfiguring the web document (home) directory is a serious error. In addition, having the path on the same drive as the system folder compounds potential attacks such as drive space exhaustion.
Fix Text
Move the web document (normally "htdocs") directory to a separate partition other than the operating system root partition and the web server’s system files.
Check Content
Run the following command: grep "DocumentRoot"<'INSTALL PATH'>/conf/httpd.conf Note each location following the "DocumentRoot" string. This is the configured path to the document root directory(s). Use the command df -k to view each document root's partition setup. Compare that against the results for the operating system file systems and against the partition for the web server system files, which is the result of the command: df -k <'INSTALL PATH'>/bin If the document root path is on the same partition as the web server system files or the operating system file systems, this is a finding.
The Apache web server must restrict the ability of users to launch denial-of-service (DoS) attacks against other information systems or networks.
Discussion
A web server can limit the ability of the web server being used in a DoS attack through several methods. The methods employed will depend upon the hosted applications and their resource needs for proper operation. An example setting that could be used to limit the ability of the web server being used in a DoS attack is bandwidth throttling.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Add or modify the "Timeout" directive in the Apache configuration to have a value of "10" seconds or less. "Timeout 10"
Check Content
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Verify that the "Timeout" directive is specified in the Apache configuration files to have a value of "10" seconds or less. If the "Timeout" directive is not configured or set for more than "10" seconds, this is a finding.
The Apache web server must display a default hosted application web page, not a directory listing, when a requested web page cannot be found.
Discussion
The goal is to completely control the web user's experience in navigating any portion of the web document root directories. Ensuring all web content directories have at least the equivalent of an index.html file is a significant factor to accomplish this end. Enumeration techniques, such as URL parameter manipulation, rely upon being able to obtain information about the Apache web server's directory structure by locating directories without default pages. In the scenario, the Apache web server will display to the user a listing of the files in the directory being accessed. By having a default hosted application web page, the anonymous web user will not obtain directory browsing information or an error message that reveals the server type and version.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Add a default document to the applicable directories.
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View the "DocumentRoot" value by entering the following command: awk '{print $1,$2,$3}' <'INSTALL PATH'>/conf/httpd.conf|grep -i DocumentRoot|grep -v '^#' Note each location following the "DocumentRoot" string. This is the configured path(s) to the document root directory(s). To view a list of the directories and subdirectories and the file "index.html", from each stated "DocumentRoot" location enter the following commands: find . -type d find . -type f -name index.html Review the results for each document root directory and its subdirectories. If a directory does not contain an "index.html" or equivalent default document, this is a finding.
Warning and error messages displayed to clients must be modified to minimize the identity of the Apache web server, patches, loaded modules, and directory paths.
Discussion
Information needed by an attacker to begin looking for possible vulnerabilities in an Apache web server includes any information about the Apache web server, backend systems being accessed, and plug-ins or modules being used. Apache web servers will often display error messages to client users, displaying enough information to aid in the debugging of the error. The information given back in error messages may display the Apache web server type, version, patches installed, plug-ins and modules installed, type of code being used by the hosted application, and any backends being used for data storage. This information could be used by an attacker to blueprint what type of attacks might be successful. The information given to users must be minimized to not aid in the blueprinting of the Apache web server.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Use the "ErrorDocument" directive to enable custom error pages. ErrorDocument 500 "Sorry, our script crashed. Oh dear" ErrorDocument 500 /cgi-bin/crash-recover ErrorDocument 500 http://error.example.com/server_error.html ErrorDocument 404 /errors/not_found.html ErrorDocument 401 /subscription/how_to_subscribe.html The syntax of the ErrorDocument directive is: ErrorDocument <3-digit-code> <action> Additional Information: https://httpd.apache.org/docs/2.4/custom-error.html
Check Content
In a command line, run "httpd -M | grep -i ssl_module". If the "ssl_module" is not enabled, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" If the "ErrorDocument" directive is not being used, this is a finding.
Debugging and trace information used to diagnose the Apache web server must be disabled.
Discussion
Information needed by an attacker to begin looking for possible vulnerabilities in a web server includes any information about the Apache web server and plug-ins or modules being used. When debugging or trace information is enabled in a production web server, information about the web server, such as web server type, version, patches installed, plug-ins and modules installed, type of code being used by the hosted application, and any backends being used for data storage, may be displayed. Since this information may be placed in logs and general messages during normal operation of the Apache web server, an attacker does not need to cause an error condition to gain access to this information.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Add or set the value of "TraceEnable" to "Off".
Check Content
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" For any enabled "TraceEnable" directives, verify they are part of the server-level configuration (i.e., not nested in a "Directory" or "Location" directive). Also verify that the "TraceEnable" directive is set to "Off". If the "TraceEnable" directive is not part of the server-level configuration and/or is not set to "Off", this is a finding. If the directive does not exist in the "conf" file, this is a finding because the default value is "On".
The Apache web server must set an absolute timeout for sessions.
Discussion
Leaving sessions open indefinitely is a major security risk. An attacker can easily use an already authenticated session to access the hosted application as the previously authenticated user. By closing sessions after an absolute period of time, the user is forced to reauthenticate, guaranteeing the session is still in use. Enabling an absolute timeout for sessions closes sessions that are still active. Examples would be a runaway process accessing the Apache web server or an attacker using a hijacked session to slowly probe the Apache web server.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Add or set the "SessionMaxAge" directive to "1".
Check Content
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Verify the "SessionMaxAge" directive exists and is set to "1". If the "SessionMaxAge" directive does not exist, this is a finding. If the "SessionMaxAge" directive exists but is not set to "1", this is a finding.
Remote access to the Apache web server must follow access policy or work in conjunction with enterprise tools designed to enforce policy requirements.
Discussion
Remote access to the Apache web server is any access that communicates through an external, non-organization-controlled network. Remote access can be used to access hosted applications or to perform management functions. The Apache web server can be accessed remotely and must be able to enforce remote access policy requirements or work in conjunction with enterprise tools designed to enforce policy requirements. Examples of the Apache web server enforcing a remote access policy are implementing IP filtering rules, using "https" instead of "http" for communication, implementing secure tokens, and validating users.
Fix Text
Ensure the web server administration is performed only over a secure path.
Check Content
If web administration is performed at the console, this check is Not Applicable. If web administration is performed remotely, the following checks will apply. If administration of the server is performed remotely, it will be performed securely and only by System Administrators. If website administration or web application administration has been delegated, those users will be documented and approved by the Information System Security Officer. Remote administration must be in compliance with any requirements contained within the Windows Server STIGs and any applicable network STIGs. Remote administration of any kind will be restricted to documented and authorized personnel. All users performing remote administration must be authenticated. All remote sessions will be encrypted and they will use FIPS 140-2 approved protocols. FIPS 140-2-approved TLS versions include TLS V1.2 or greater. Review with site management how remote administration, if applicable, is configured on the website. If remote management meets the criteria listed above, this is not a finding. If remote management is used and does not meet the criteria listed above, this is a finding.
The Apache web server must restrict inbound connections from nonsecure zones.
Discussion
Remote access to the Apache web server is any access that communicates through an external, non-organization-controlled network. Remote access can be used to access hosted applications or to perform management functions. A web server can be accessed remotely and must be capable of restricting access from what the DoD defines as nonsecure zones. Nonsecure zones are defined as any IP, subnet, or region that is defined as a threat to the organization. The nonsecure zones must be defined for public web servers logically located in a DMZ, as well as private web servers with perimeter protection devices. By restricting access from nonsecure zones, through the internal web server access list, the Apache web server can stop or slow denial-of-service (DoS) attacks on the web server.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Configure the "httpd.conf" file to include restrictions. Example: <RequireAll> Require not host phishers.example.com moreidiots.example </RequireAll>
Check Content
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" If "IP Address Restrictions" are not configured or IP ranges configured to "Allow" are not restrictive enough to prevent connections from nonsecure zones, this is a finding.
Non-privileged accounts on the hosting system must only access Apache web server security-relevant information and functions through a distinct administrative account.
Discussion
By separating Apache web server security functions from non-privileged users, roles can be developed that can then be used to administer the Apache web server. Forcing users to change from a non-privileged account to a privileged account when operating on the Apache web server or on security-relevant information forces users to only operate as a Web Server Administrator when necessary. Operating in this manner allows for better logging of changes and better forensic information and limits accidental changes to the Apache web server.
Fix Text
Restrict access to the web administration tool to only the System Administrator, Web Manager, or the Web Manager designees.
Check Content
Determine which tool or control file is used to control the configuration of the web server. If the control of the web server is done via control files, verify who has update access to them. If tools are being used to configure the web server, determine who has access to execute the tools. If accounts other than the System Administrator, Web Manager, or the Web Manager designees have access to the web administration tool or control files, this is a finding.
The Apache web server application, libraries, and configuration files must only be accessible to privileged users.
Discussion
The Apache web server can be modified through parameter modification, patch installation, upgrades to the Apache web server or modules, and security parameter changes. With each of these changes, there is the potential for an adverse effect such as a denial of service (DoS), Apache web server instability, or hosted application instability. To limit changes to the Apache web server and limit exposure to any adverse effects from the changes, files such as the Apache web server application files, libraries, and configuration files must have permissions and ownership set properly to only allow privileged users access.
Fix Text
Ensure non-administrators are not allowed access to the directory tree, the shell, or other operating system functions and utilities.
Check Content
Obtain a list of the user accounts for the system, noting the privileges for each account. Verify with the System Administrator (SA) or the Information System Security Officer (ISSO) that all privileged accounts are mission essential and documented. Verify with the SA or the ISSO that all non-administrator access to shell scripts and operating system functions are mission essential and documented. If undocumented privileged accounts are found, this is a finding. If undocumented access to shell scripts or operating system functions is present, this is a finding.
The Apache web server must only accept client certificates issued by DoD PKI or DoD-approved PKI Certification Authorities (CAs).
Discussion
Non-DoD approved PKIs have not been evaluated to ensure that they have security controls and identity vetting procedures in place that are sufficient for DoD systems to rely on the identity asserted in the certificate. PKIs lacking sufficient security controls and identity vetting procedures risk being compromised and issuing certificates that enable adversaries to impersonate legitimate users.
Fix Text
Configure the web server’s trust store to trust only DoD-approved PKIs (e.g., DoD PKI, DoD ECA, and DoD-approved external partners).
Check Content
Determine the location of the "HTTPD_ROOT" directory and the "ssl.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" Go into <'HTTPD_ROOT'>/conf.d/ssl.conf Look for the "SSLCACertificateFile" directive. Review the path of the "SSLCACertificateFile" directive. Review the contents of <'path of cert'>\ca-bundle.crt Examine the contents of this file to determine if the trusted CAs are DoD approved. If the trusted CA that is used to authenticate users to the website does not lead to an approved DoD CA, this is a finding. NOTE: There are non-DoD roots that must be on the server for it to function. Some applications, such as antivirus programs, require root CAs to function. DoD approved certificate can include the External Certificate Authorities (ECA), if approved by the AO. The PKE InstallRoot 3.06 System Administrator Guide (SAG), dated 08 Jul 2008, contains a complete list of DoD, ECA, and IECA CAs.
The Apache web server private website must employ cryptographic mechanisms (TLS) and require client certificates.
Discussion
When data is written to digital media, such as hard drives, mobile computers, external/removable hard drives, personal digital assistants, flash/thumb drives, etc., there is risk of data loss and data compromise. User identities and passwords stored on the hard drive of the hosting hardware must be encrypted to protect the data from easily being discovered and used by an unauthorized user to access the hosted applications. The cryptographic libraries and functionality used to store and retrieve the user identifiers and passwords must be part of the web server. Preventing the disclosure of transmitted information requires that the web server take measures to employ some form of cryptographic mechanism to protect the information during transmission. This is usually achieved through the use of Transport Layer Security (TLS). Transmission of data can take place between the web server and a large number of devices/applications external to the web server. Examples are a web client used by a user, a backend database, an audit server, or other web servers in a web cluster. If data is transmitted unencrypted, the data then becomes vulnerable to disclosure. The disclosure may reveal user identifier/password combinations, website code revealing business logic, or other user personal information. Also satisfies: SRG-APP-000439-WSR-000151.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Ensure the "SSLProtocol" is added and looks like the following: SSLProtocol -ALL +TLSv1.2 Restart Apache: apachectl restart
Check Content
In a command line, run "httpd -M | grep -i ssl_module". If the "ssl_module" is not enabled, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Search for the directive "SSLProtocol" in the "httpd.conf" file: # cat /<path_to_file>/httpd.conf | grep -i "SSLProtocol" If the "SSLProtocol" directive is missing or does not look like the following, this is a finding: SSLProtocol -ALL +TLSv1.2 If the TLS version is not TLS 1.2 or higher, according to NIST SP 800-52 Rev 2, or if non-FIPS-approved algorithms are enabled, this is a finding. NOTE: In some cases, web servers are configured in an environment to support load balancing. This configuration most likely uses a content switch to control traffic to the various web servers. In this situation, the TLS certificate for the websites may be installed on the content switch versus the individual websites. This solution is acceptable as long as the web servers are isolated from the general population LAN. Users should not have the ability to bypass the content switch to access the websites.
The Apache web server must be tuned to handle the operational requirements of the hosted application.
Discussion
A denial of service (DoS) can occur when the Apache web server is so overwhelmed that it can no longer respond to additional requests. A web server not properly tuned may become overwhelmed and cause a DoS condition even with expected traffic from users. To avoid a DoS, the Apache web server must be tuned to handle the expected traffic for the hosted applications.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Add or modify the "Timeout" directive in the Apache configuration to have a value of "10" seconds or less. "Timeout 10"
Check Content
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Verify the "Timeout" directive is specified in the Apache configuration files to have a value of "10" seconds or less. If the "Timeout" directive is not configured or set for more than "10" seconds, this is a finding.
The Apache web server must employ cryptographic mechanisms (TLS/DTLS/SSL) preventing the unauthorized disclosure of information during transmission.
Discussion
Preventing the disclosure of transmitted information requires that the Apache web server take measures to employ some form of cryptographic mechanism to protect the information during transmission. This is usually achieved through the use of Transport Layer Security (TLS). Transmission of data can take place between the Apache web server and a large number of devices/applications external to the Apache web server. Examples are a web client used by a user, a backend database, an audit server, or other web servers in a web cluster. If data is transmitted unencrypted, the data then becomes vulnerable to disclosure. The disclosure may reveal user identifier/password combinations, website code revealing business logic, or other user personal information.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Ensure the "SSLProtocol" is added and looks like the following: SSLProtocol -ALL +TLSv1.2 Restart Apache: apachectl restart
Check Content
In a command line, run "httpd -M | grep -i ssl_module". If the "ssl_module" is not enabled, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Search for the directive "SSLProtocol" in the "httpd.conf" file: # cat /<path_to_file>/httpd.conf | grep -i "SSLProtocol" If the "SSLProtocol" directive is missing or does not look like the following, this is a finding. SSLProtocol -ALL +TLSv1.2 If the TLS version is not TLS 1.2 or higher, according to NIST SP 800-52 Rev 2, or if non-FIPS-approved algorithms are enabled, this is a finding. NOTE: In some cases, web servers are configured in an environment to support load balancing. This configuration most likely uses a content switch to control traffic to the various web servers. In this situation, the TLS certificate for the websites may be installed on the content switch versus the individual websites. This solution is acceptable as long as the web servers are isolated from the general population LAN. Users should not have the ability to bypass the content switch to access the websites.
The Apache web server session IDs must be sent to the client using SSL/TLS.
Discussion
The HTTP protocol is a stateless protocol. To maintain a session, a session identifier is used. The session identifier is a piece of data that is used to identify a session and a user. If the session identifier is compromised by an attacker, the session can be hijacked. By encrypting the session identifier, the identifier becomes more difficult for an attacker to hijack, decrypt, and use before the session has expired.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Ensure the "SSLProtocol" is added and looks like the following: SSLProtocol -ALL +TLSv1.2 Restart Apache: apachectl restart
Check Content
In a command line, run "httpd -M | grep -i ssl_module". If the "ssl_module" is not enabled, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Search for the directive "SSLProtocol" in the "httpd.conf" file: # cat /<path_to_file>/httpd.conf | grep -i "SSLProtocol" If the "SSLProtocol" directive is missing or does not look like the following, this is a finding. SSLProtocol -ALL +TLSv1.2 If the TLS version is not TLS 1.2 or higher, according to NIST SP 800-52 Rev 2, or if non-FIPS-approved algorithms are enabled, this is a finding. NOTE: In some cases, web servers are configured in an environment to support load balancing. This configuration most likely uses a content switch to control traffic to the various web servers. In this situation, the TLS certificate for the websites may be installed on the content switch versus the individual websites. This solution is acceptable as long as the web servers are isolated from the general population LAN. Users should not have the ability to bypass the content switch to access the websites.
The Apache web server cookies, such as session cookies, sent to the client using SSL/TLS must not be compressed.
Discussion
A cookie is used when a web server needs to share data with the client's browser. The data is often used to remember the client when the client returns to the hosted application at a later date. A session cookie is a special type of cookie used to remember the client during the session. The cookie will contain the session identifier (ID) and may contain authentication data to the hosted application. To protect this data from easily being compromised, the cookie can be encrypted. When a cookie is sent encrypted via SSL/TLS, an attacker must spend a great deal of time and resources to decrypt the cookie. If, along with encryption, the cookie is compressed, the attacker can now use a combination of plaintext injection and inadvertent information leakage through data compression to reduce the time needed to decrypt the cookie. This attack is called Compression Ratio Info-leak Made Easy (CRIME). Cookies shared between the Apache web server and the client when encrypted should not also be compressed.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Ensure the "SSLCompression" is added and looks like the following: SSLCompression off Restart Apache: apachectl restart
Check Content
In a command line, run "httpd -M | grep -i ssl_module". If "ssl_module" is not listed, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" If the "SSLCompression" directive does not exist or is set to "on", this is a finding.
Cookies exchanged between the Apache web server and the client, such as session cookies, must have cookie properties set to prohibit client-side scripts from reading the cookie data.
Discussion
A cookie can be read by client-side scripts easily if cookie properties are not set properly. By allowing cookies to be read by the client-side scripts, information such as session identifiers could be compromised and used by an attacker who intercepts the cookie. Setting cookie properties (i.e., HttpOnly property) to disallow client-side scripts from reading cookies better protects the information inside the cookie.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Set "Session" to "on". Ensure the "SessionCookieName" directive includes "httpOnly" and "secure".
Check Content
In a command line, run "httpd -M | grep -i session_cookie_module". Review the "httpd.conf" file. If the "Session" and "SessionCookieName" directives are not present, this is a finding. If "Session" is not "on" and "SessionCookieName" does not contain "httpOnly" and "secure", this is a finding.
Cookies exchanged between the Apache web server and the client, such as session cookies, must have cookie properties set to force the encryption of cookies.
Discussion
Cookies can be sent to a client using TLS/SSL to encrypt the cookies, but TLS/SSL is not used by every hosted application since the data being displayed does not require the encryption of the transmission. To safeguard against cookies, especially session cookies, being sent in plaintext, a cookie can be encrypted before transmission. To force a cookie to be encrypted before transmission, the cookie "Secure" property can be set.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Set "Session" to "on". Ensure the "SessionCookieName" directive includes "httpOnly" and "secure".
Check Content
In a command line, run "httpd -M | grep -i session_cookie_module". If "session_cookie_module" is not listed, this is a finding. Review the "httpd.conf" file. If the "Session" and "SessionCookieName" directives are not present, this is a finding. If "Session" is not "on" and "SessionCookieName" does not contain "httpOnly" and "secure", this is a finding.
An Apache web server must maintain the confidentiality of controlled information during transmission through the use of an approved TLS version.
Discussion
Transport Layer Security (TLS) is a required transmission protocol for a web server hosting controlled information. The use of TLS provides confidentiality of data in transit between the web server and client. FIPS 140-2 approved TLS versions must be enabled and non-FIPS-approved SSL versions must be disabled. NIST SP 800-52 defines the approved TLS versions for government applications.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Ensure the "SSLProtocol" is added and looks like the following: SSLProtocol -ALL +TLSv1.2 Restart Apache: apachectl restart
Check Content
In a command line, run "httpd -M | grep -i ssl_module". If the "ssl_module" is not enabled, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Search for the directive "SSLProtocol" in the "httpd.conf" file: # cat /<path_to_file>/httpd.conf | grep -i "SSLProtocol" If the "SSLProtocol" directive is missing or does not look like the following, this is a finding: SSLProtocol -ALL +TLSv1.2 If the TLS version is not TLS 1.2 or higher, according to NIST SP 800-52 Rev 2, or if non-FIPS-approved algorithms are enabled, this is a finding. NOTE: In some cases, web servers are configured in an environment to support load balancing. This configuration most likely uses a content switch to control traffic to the various web servers. In this situation, the TLS certificate for the websites may be installed on the content switch versus the individual websites. This solution is acceptable as long as the web servers are isolated from the general population LAN. Users should not have the ability to bypass the content switch to access the websites.
The Apache web server must maintain the confidentiality and integrity of information during preparation for transmission.
Discussion
Information can be either unintentionally or maliciously disclosed or modified during preparation for transmission, including, for example, during aggregation, at protocol transformation points, and during packing/unpacking. These unauthorized disclosures or modifications compromise the confidentiality or integrity of the information. An example of this would be an SMTP queue. This queue may be added to an Apache web server through an SMTP module to enhance error reporting or to allow developers to add SMTP functionality to their applications. Any modules used by the Apache web server that queue data before transmission must maintain the confidentiality and integrity of the information before the data is transmitted.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Ensure the "SSLProtocol" is added and looks like the following: SSLProtocol -ALL +TLSv1.2 Restart Apache: apachectl restart
Check Content
In a command line, run "httpd -M | grep -i ssl_module". If the "ssl_module" is not enabled, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Search for the directive "SSLProtocol" in the "httpd.conf" file: # cat /<path_to_file>/httpd.conf | grep -i "SSLProtocol" If the "SSLProtocol" directive is missing or does not look like the following, this is a finding: SSLProtocol -ALL +TLSv1.2 If the TLS version is not TLS 1.2 or higher, according to NIST SP 800-52 Rev 2, or if non-FIPS-approved algorithms are enabled, this is a finding. NOTE: In some cases, web servers are configured in an environment to support load balancing. This configuration most likely uses a content switch to control traffic to the various web servers. In this situation, the TLS certificate for the websites may be installed on the content switch versus the individual websites. This solution is acceptable as long as the web servers are isolated from the general population LAN. Users should not have the ability to bypass the content switch to access the websites.
The Apache web server must maintain the confidentiality and integrity of information during reception.
Discussion
Information can be either unintentionally or maliciously disclosed or modified during reception, including, for example, during aggregation, at protocol transformation points, and during packing/unpacking. These unauthorized disclosures or modifications compromise the confidentiality or integrity of the information. Protecting the confidentiality and integrity of received information requires that application servers take measures to employ approved cryptography to protect the information during transmission over the network. This is usually achieved through the use of Transport Layer Security (TLS), SSL VPN, or IPsec tunnel. The Apache web server must use approved encryption when receiving transmitted data.
Fix Text
Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Ensure the "SSLProtocol" is added and looks like the following: SSLProtocol -ALL +TLSv1.2 Restart Apache: apachectl restart
Check Content
In a command line, run "httpd -M | grep -i ssl_module". If the "ssl_module" is not enabled, this is a finding. Determine the location of the "HTTPD_ROOT" directory and the "httpd.conf" file: # httpd -V | egrep -i 'httpd_root|server_config_file' -D HTTPD_ROOT="/etc/httpd" -D SERVER_CONFIG_FILE="conf/httpd.conf" Search for the directive "SSLProtocol" in the "httpd.conf" file: # cat /<path_to_file>/httpd.conf | grep -i "SSLProtocol" If the "SSLProtocol" directive is missing or does not look like the following, this is a finding: SSLProtocol -ALL +TLSv1.2 If the TLS version is not TLS 1.2 or higher, according to NIST SP 800-52 Rev 2, or if non-FIPS-approved algorithms are enabled, this is a finding. NOTE: In some cases, web servers are configured in an environment to support load balancing. This configuration most likely uses a content switch to control traffic to the various web servers. In this situation, the TLS certificate for the websites may be installed on the content switch versus the individual websites. This solution is acceptable as long as the web servers are isolated from the general population LAN. Users should not have the ability to bypass the content switch to access the web sites.
The Apache web server must be configured in accordance with the security configuration settings based on DoD security configuration or implementation guidance, including STIGs, NSA configuration guides, CTOs, and DTMs.
Discussion
Configuring the Apache web server to implement organization-wide security implementation guides and security checklists guarantees compliance with federal standards and establishes a common security baseline across the DoD that reflects the most restrictive security posture consistent with operational requirements. Configuration settings are the set of parameters that can be changed that affect the security posture and/or functionality of the system. Security-related parameters are parameters impacting the security state of the Apache web server, including the parameters required to satisfy other security control requirements.
Fix Text
Ensure the website enforces the use of IANA well-known ports for HTTP and HTTPS.
Check Content
Review the website to determine if HTTP and HTTPs are used in accordance with well-known ports (e.g., 80 and 443) or those ports and services as registered and approved for use by the DoD PPSM. Verify that any variation in PPS is documented, registered, and approved by the PPSM. If well-known ports and services are not approved for used by PPSM, this is a finding.