# CVE-2026-123599: Hickory DNS before 0.26.0-beta.1 DNSSEC Validation Bypass via Non-IN Class Records

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

Hickory DNS hickory-proto before 0.26.0-beta.1 and hickory-net before 0.26.2 contain a DNSSEC validation bypass because verify_rrsets() ignores DNS class when partitioning RRsets, so non-IN records skip signature verification yet are marked secure when the IN records verify. Attackers able to supply DNS responses can include forged CH or HS class records, including DS records, to authenticate any DNSKEY and forge child zone responses.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- hickory-dns / hickory-dns (hickory-proto): ≥ 0; < 0.26.0-beta.1 (affected, semver); 0.26.0-beta.1 (unaffected, semver). Source: CNA: VulnCheck
- hickory-dns / hickory-dns (hickory-net): ≥ 0.26.0-beta.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:N/SC:N/SI:N/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 3.7 (low); CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N; source: CNA: VulnCheck

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-345

## 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-wjgj-fvg9-65w9 (CNA: VulnCheck; vendor-advisory)

- https://www.vulncheck.com/advisories/hickory-dns-before-0.26.0-beta.1-dnssec-validation-bypass-via-non-in-class-records (CNA: VulnCheck; third-party-advisory)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-123599; retrieved 2026-11-08; source updated 2026-11-08

Revision: d17b878ee9d96e71b164e4cfd62664169dc08d699621025064ecab76af48e536

Canonical: https://y2.dev/cve/CVE-2026-123599

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