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CNAME records must not point to a zone with lesser security for more than six months.

Overview

Finding IDVersionRule IDIA ControlsSeverity
V-279956SRG-APP-000243-DNS-000114SV-279956r1156977_ruleCCI-001090medium
Description
The use of CNAME records for exercises, tests, or zone-spanning aliases should be temporary (e.g., to facilitate a migration). When a host name is an alias for a record in another zone, an adversary has two points of attack: the zone in which the alias is defined and the zone authoritative for the alias's canonical name. This configuration also reduces the speed of client resolution because it requires a second lookup after obtaining the canonical name. Furthermore, in the case of an authoritative name server, this information is promulgated throughout the enterprise to caching servers and thus compounds the vulnerability.
STIGDate
Domain Name System (DNS) Security Requirements Guide2025-12-19

Related Frameworks

1 mapping across 5 frameworks
SCF0 mappings

No source states a mapping between these directly.

Also reachable in 3 hops (13) derived by us, not asserted by any source

Each of these is a route we composed by chaining published mappings. No publisher states a relationship between the two endpoints.

CFG-02Secure Baseline Configurations
1.00
CRY-01Use of Cryptographic Controls
1.00
CRY-01.1Alternate Physical Protection
1.00
CRY-03Transmission Confidentiality
1.00
CRY-04Transmission Integrity
1.00
CRY-05Encrypting Data At Rest
1.00
DCH-01Data Protection
1.00
IAC-21Least Privilege
1.00
NET-01Network Security Controls (NSC)
1.00
NET-02Layered Network Defenses
1.00

+3 more (top 10 by confidence shown)

NIST 800-530 mappings

No source states a mapping between these directly.

Also reachable in 2 hops (35) derived by us, not asserted by any source

Each of these is a route we composed by chaining published mappings. No publisher states a relationship between the two endpoints.

AC-2(1)Automated System Account Management
1.00
AC-2(10)Shared and Group Account Credential Change
1.00
AC-2(2)Automated Temporary and Emergency Account Management
1.00
AC-2(3)Disable Accounts
1.00
AC-2(4)Automated Audit Actions
1.00
AC-3Access Enforcement
1.00
AC-4Information Flow Enforcement
1.00
AC-6(10)Prohibit Non-privileged Users from Executing Privileged Functions
1.00
AC-6(8)Privilege Levels for Code Execution
1.00
AC-7Unsuccessful Logon Attempts
1.00

+25 more (top 10 by confidence shown)

NIST 800-1710 mappings

No source states a mapping between these directly.

Also reachable in 3 hops (1) derived by us, not asserted by any source

Each of these is a route we composed by chaining published mappings. No publisher states a relationship between the two endpoints.

3.13.4
1.00
CCI1 mapping
CCI-001090
1.00
NIST CSF 2.00 mappings

No source states a mapping between these directly.

Also reachable in 3 hops (4) derived by us, not asserted by any source

Each of these is a route we composed by chaining published mappings. No publisher states a relationship between the two endpoints.

PR.DS-01
1.00
PR.DS-02
1.00
PR.DS-10
1.00
PR.IR-01
1.00

Who does this work

13 NICE work roles and 8 EC-Council certifications.

This is an inference across published mappings, not a single claim by anyone. This check maps to a control, which maps to a Cybersecurity Framework outcome, which NIST assigns to the work roles below. EC-Council separately maps its certifications to those same roles.

A certification prepares someone for a role. It is not evidence that a holder is qualified, and neither NIST nor EC-Council has stated that any certification here addresses this check.

Work-role assignments published by NIST (NICE Framework Components 2.2.0 and the CSF 2.0 OLIR crosswalk). Certification mappings published by EC-Council.

Details

Check Text (C-279956r1156977_chk)

Review the DNS server's hosted zones and respective records. Within the zone statement will be a file option that will display the name of the zone file. The record type column will display CNAME. This is usually the third or fourth field in a record depending on whether the TTL value is utilized. Without a TTL value, the CNAME type will be in the third field; otherwise, it will display as the fourth field. Review the zone files and the DNS zone record documentation to confirm that there are no CNAME records older than 6 months. The exceptions are glue records supporting zone delegations, CNAME records supporting a system migration, or CNAME records that point to third party Content Delivery Networks (CDN) or cloud computing platforms. In the case of third-party CDNs or cloud offerings, an approved mission need must be demonstrated (AO approval of use of a commercial cloud offering would satisfy this requirement). If there are zone-spanning CNAME records older than 6 months and the CNAME records resolves to anything other than fully qualified domain name for glue records supporting zone delegations, CNAME records supporting a system migration, or CNAME records that point to third-party Content Delivery Networks (CDN) or cloud computing platforms with a AO-approved and documented mission need, this is a finding.

Fix Text (F-84422r1156976_fix)

Remove any zone-spanning CNAME records that have been active for more than six months.