CVE-2026-13321

The BIND resolver accepts validly-signed NSEC records where the "Next Domain Name" field points outside the signer's zone.

An attacker controlling any DNSSEC-signed zone can craft NSEC records that span into victim zones, enabling cross-zone cache poisoning with authenticated denial-of-service responses (AD=1).

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Disclaimer: The following mitigation notes are provided as a courtesy, pending the application of an official patch. This content was generated utilizing AI tools in conjunction with data from cmetaxonomy.org. Customers are advised to independently evaluate and test these temporary mitigations within their own infrastructure.

ISC states no workarounds exist. Until patched, restrict the resolver to authorized client networks and deploy separate resolvers per trust zone. Memory hardening and auth controls don't apply — this is a DNS protocol logic error using validly-signed records.