{"id":"CVE-2026-123594","title":"Hickory DNS through 0.26.0-alpha.1 DNSSEC NSEC Validation Bypass for Empty Non-Terminals","summary":"Hickory DNS hickory-proto through 0.26.0-alpha.1 and hickory-net 0.26.0-beta.1 before 0.26.2 contain an NSEC validation flaw that returns a secure proof for NXDOMAIN responses when the covering NSEC's Next Domain Name is a strict descend…","severity":"medium","cvss":4.8,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L","cvssSource":"cna","cwe":["CWE-345"],"vendor":"hickory-dns","product":"hickory-dns","affected":["hickory-dns <= 0.26.0-alpha.1","hickory-dns >= 0.26.0-beta.1 < 0.26.2"],"published":"2026-11-08","updated":"2026-11-08","sourceUpdated":"2026-11-08T01:38:24.397Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-123594","references":[{"url":"https://github.com/hickory-dns/hickory-dns/security/advisories/GHSA-86vr-jm6c-7cpg","label":"GitHub Security Advisory (GHSA-86vr-jm6c-7cpg)"},{"url":"https://www.vulncheck.com/advisories/hickory-dns-through-0.26.0-alpha.1-dnssec-nsec-validation-bypass-for-empty-non-terminals","label":"VulnCheck Advisory: Hickory DNS through 0.26.0-alpha.1 DNSSEC NSEC Validation Bypass for Empty Non-Terminals"}],"tags":["cve.org"],"ingestedAt":"2026-11-08T02:43:18.644Z","slug":"CVE-2026-123594","body":"## Overview\n\nHickory DNS hickory-proto through 0.26.0-alpha.1 and hickory-net 0.26.0-beta.1 before 0.26.2 contain an NSEC validation flaw that returns a secure proof for NXDOMAIN responses when the covering NSEC's Next Domain Name is a strict descendant of the query name, which actually proves the name exists as an empty non-terminal. On-path attackers can flip the unsigned rcode of a genuine signed NODATA response from NOERROR to NXDOMAIN, causing validators to accept forged nonexistence of the name.\n\n## Affected\n\n- `hickory-dns <= 0.26.0-alpha.1`\n- `hickory-dns >= 0.26.0-beta.1 < 0.26.2`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":26,"depthScoreParts":{"impact":26.4,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}