{"id":"CVE-2026-123591","title":"Hickory DNS 0.26.0-beta.1 before 0.26.2 DNSSEC Validation Bypass via Missing RFC 6840 Checks","summary":"Hickory DNS hickory-net 0.26.0-beta.1 before 0.26.2 and hickory-proto through 0.26.0-alpha.1 fail to verify, per RFC 6840 §4.4, that an NSEC or NSEC3 record denying a DS RRset also proves the delegation's NS record exists. Attackers can …","severity":"medium","cvss":5.9,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N","cvssSource":"cna","cwe":["CWE-345"],"vendor":"hickory-dns","product":"hickory-dns","affected":["hickory-dns >= 0.26.0-beta.1 < 0.26.2","hickory-dns <= 0.26.0-alpha.1"],"published":"2026-11-08","updated":"2026-11-08","sourceUpdated":"2026-11-08T01:38:22.338Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-123591","references":[{"url":"https://github.com/hickory-dns/hickory-dns/security/advisories/GHSA-7php-9j59-g3ch","label":"GitHub Security Advisory (GHSA-7php-9j59-g3ch)"},{"url":"https://www.vulncheck.com/advisories/hickory-dns-0.26.0-beta.1-before-0.26.2-dnssec-validation-bypass-via-missing-rfc-6840-checks","label":"VulnCheck Advisory: Hickory DNS 0.26.0-beta.1 before 0.26.2 DNSSEC Validation Bypass via Missing RFC 6840 Checks"}],"tags":["cve.org"],"ingestedAt":"2026-11-08T02:43:18.646Z","slug":"CVE-2026-123591","body":"## Overview\n\nHickory DNS hickory-net 0.26.0-beta.1 before 0.26.2 and hickory-proto through 0.26.0-alpha.1 fail to verify, per RFC 6840 §4.4, that an NSEC or NSEC3 record denying a DS RRset also proves the delegation's NS record exists. Attackers can reuse child-side NSEC or NSEC3 records to fake an insecure delegation and forge child-zone records.\n\n## Affected\n\n- `hickory-dns >= 0.26.0-beta.1 < 0.26.2`\n- `hickory-dns <= 0.26.0-alpha.1`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":32,"depthScoreParts":{"impact":32.5,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}