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V-72471

A BIND 9.x server implementation must maintain the integrity and confidentiality of DNS information while it is being prepared for transmission, in transmission, and in use and t must perform integrity verification and data origin verification for all DNS information.

Finding ID
BIND-9X-001200
Rule ID
SV-87095r2_rule
Severity
Cat I
CCE
(None)
Group Title
SRG-APP-000213-DNS-000024
CCI
CCI-002468
Target Key
(None)
Documentable
No
Discussion

DNSSEC is required for securing the DNS query/response transaction by providing data origin authentication and data integrity verification through signature verification and the chain of trust Failure to accomplish data origin authentication and data integrity verification could have significant effects on DNS Infrastructure. The resultant response could be forged, it may have come from a poisoned cache, the packets could have been intercepted without the resolver's knowledge, or resource records could have been removed that would result in query failure or denial of service Failure to validate name server replies would cause many networking functions and communications to be adversely affected. With DNS, the presence of Delegation Signer (DS) records associated with child zones informs clients of the security status of child zones. These records are crucial to the DNSSEC chain of trust model. Each parent domain's DS record is used to verify the DNSKEY record in its subdomain, from the top of the DNS hierarchy down. Failure to validate the chain of trust used with DNSSEC would have a significant impact on the security posture of the DNS server. Non-validated trust chains may contain rouge DNS servers and allow those unauthorized servers to introduce invalid data into an organizations DNS infrastructure. A compromise of this type would be difficult to detect and may have devastating effects on the validity and integrity of DNS zone information. Satisfies: SRG-APP-000213-DNS-000024, SRG-APP-000215-DNS-000026, SRG-APP-000219-DNS-000028, SRG-APP-000219-DNS-000029, SRG-APP-000219-DNS-000030, SRG-APP-000347-DNS-000041, SRG-APP-000348-DNS-000042, SRG-APP-000349-DNS-000043, SRG-APP-000420-DNS-000053, SRG-APP-000421-DNS-000054, SRG-APP-000422-DNS-000055, SRG-APP-000423-DNS-000056, SRG-APP-000424-DNS-000057, SRG-APP-000425-DNS-000058, SRG-APP-000426-DNS-000059, SRG-APP-000441-DNS-000066, SRG-APP-000442-DNS-000067, SRG-APP-000516-DNS-000089

Fix Text

Set the "dnssec-enable" option to yes. Sign each zone file that the name server is responsible for. Configure each zone the name server is responsible for to use a DNSSEC signed zone.

Check Content

If the server is in a classified network, this is Not Applicable. Verify that DNSSEC is enabled. Inspect the "named.conf" file for the following: dnssec-enable yes; If "dnssec-enable" does not exist or is not set to "yes", this is a finding. Verify that each zone on the name server has been signed. Identify each zone file that the name sever is responsible for and search each file for the "DNSKEY" entries: # less <signed_zone_file> 86400 DNSKEY 257 3 8 ( HASHED_KEY ) ; KSK; alg = RSASHA256; key id = 31225 86400 DNSKEY 256 3 8 ( HASHED_KEY ) ; ZSK; alg = RSASHA256; key id = 52179 Ensure that there are separate "DNSKEY" entries for the "KSK" and the "ZSK" If the "DNSKEY" entries are missing, the zone file is not signed. If the zone files are not signed, this is a finding.