# CVE-2026-123600: Hickory DNS hickory-proto 0.25.0-alpha.3 through 0.25.2 NSEC3 Apex NODATA Validation Bypass

Status: published. Published: 2026-11-08. Updated: 2026-11-08.

Hickory DNS hickory-proto 0.25.0-alpha.3 through 0.25.2 and hickory-net 0.26.0-alpha.1 before 0.26.2 contain a DNSSEC validation flaw in DnssecDnsHandle that accepts NSEC3-signed NODATA responses for zone-apex queries as secure without an NSEC3 record matching the hashed QNAME. On-path attackers or malicious authoritative servers can replay a validly signed non-apex NSEC3 with the zone's signed SOA to serve an authenticated (AD=1) denial of any apex RRtype for the negative-cache TTL.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- hickory-dns / hickory-dns (hickory-proto): ≥ 0.25.0-alpha.3; ≤ 0.25.2 (affected, semver). Source: CNA: VulnCheck
- hickory-dns / hickory-dns (hickory-net): ≥ 0.26.0-alpha.1; < 0.26.2 (affected, semver); 0.26.2 (unaffected, semver). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 6.3 (medium); CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 4.8 (medium); CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L; source: CNA: VulnCheck

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-358

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/hickory-dns/hickory-dns/security/advisories/GHSA-3jvh-8vj5-65rq (CNA: VulnCheck; vendor-advisory)

- https://www.vulncheck.com/advisories/hickory-dns-hickory-proto-0.25.0-alpha.3-through-0.25.2-nsec3-apex-nodata-validation-bypass (CNA: VulnCheck; third-party-advisory)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-123600; retrieved 2026-11-08; source updated 2026-11-08

Revision: 78ad64351fcd15487c8f9a847b4eb3eaaf039e13172fc704450149b080902463

Canonical: https://y2.dev/cve/CVE-2026-123600

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