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NIST SP 800-53 Rev. 5 · SC-20

Secure Name/Address Resolution Service (Authoritative Source)

US National Institute of Standards and Technology (NIST) · cited in 15 of our lessons

Explanation

What it asks for. Authoritative name resolution services must provide data origin authentication and integrity verification artifacts with their responses, and support verification of chains of trust when operating as part of a distributed hierarchical namespace.

In practice. This mostly means signing your authoritative DNS zones with DNSSEC and maintaining the chain of trust with the parent zone. Good practice includes managed key rollover, monitoring for signing failures and protection of DNS registrar and hosting accounts with strong authentication. Auditors look for DNSSEC validation results, key management procedures and registrar security settings.

Common gaps. Many organisations have not enabled DNSSEC on their zones, or let signatures expire. Registrar accounts protected only by passwords remain a common route to domain hijacking.

Open SP 800-53 at NIST
The official text
a. Provide additional data origin authentication and integrity verification artifacts along with the authoritative name resolution data the system returns in response to external name/address resolution queries; and b. Provide the means to indicate the security status of child zones and (if the child supports secure resolution services) to enable verification of a chain of trust among parent and child domains, when operating as part of a distributed, hierarchical namespace. Discussion: Providing authoritative source information enables external clients, including remote Internet clients, to obtain origin authentication and integrity verification assurances for the host/service name to network address resolution information obtained through the service. Systems that provide name and address resolution services include domain name system (DNS) servers. Additional artifacts include DNS Security Extensions (DNSSEC) digital signatures and cryptographic keys. Authoritative data includes DNS resource records. The means for indicating the security status of child zones include the use of delegation signer resource records in the DNS. Systems that use technologies other than the DNS to map between host and service names and network addresses provide other means to assure the authenticity and integrity of response data.

From NIST SP 800-53 Rev. 5, a work of the US government in the public domain.

Lessons that cite it

Real incidents where this item mattered: the latest 12 of 15.