# CVE-2026-123585: Hickory DNS 0.25.0 before 0.26.2 Query Amplification via Irrelevant CNAME Records

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

The hickory-resolver component of Hickory DNS 0.25.0 before 0.26.2 follows irrelevant CNAME records when resolving recursive queries, sending queries that are unnecessary to answer the original request. Attackers controlling DNS responses can include CNAME records in the authority or additional sections, or outside the original query name's CNAME chain, causing excess resolver queries and increased query amplification.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- hickory-dns / hickory-dns (hickory-resolver): ≥ 0.25.0; < 0.26.2 (affected, semver); 0.26.2 (unaffected, semver). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 6.9 (medium); CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 5.3 (medium); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L; source: CNA: VulnCheck

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-400

## 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-6f2x-v7q7-m7m5 (CNA: VulnCheck; vendor-advisory)

- https://www.vulncheck.com/advisories/hickory-dns-0.25.0-before-0.26.2-query-amplification-via-irrelevant-cname-records (CNA: VulnCheck; third-party-advisory)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-123585; retrieved 2026-11-08; source updated 2026-11-08

Revision: 6b8d3c9bdd41d5e4fc4da33c428e736f583fe0949786c71e040214bd72e5cfac

Canonical: https://y2.dev/cve/CVE-2026-123585

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