{"id":"CVE-2026-123594","published":"2026-11-08T02:16:53.710","lastModified":"2026-11-10T22:15:59.797","description":"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 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.","cvssScore":4.8,"cvssSeverity":"MEDIUM","cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L","cwes":["CWE-345"],"vendors":[],"products":[],"references":[{"url":"https://github.com/hickory-dns/hickory-dns/security/advisories/GHSA-86vr-jm6c-7cpg","tags":[]},{"url":"https://www.vulncheck.com/advisories/hickory-dns-through-0.26.0-alpha.1-dnssec-nsec-validation-bypass-for-empty-non-terminals","tags":[]}],"exploitRefs":[{"url":"https://github.com/hickory-dns/hickory-dns/security/advisories/GHSA-86vr-jm6c-7cpg","tags":[]}],"hasPoc":true,"ai":null}