# CVE-2026-123587: Hickory-DNS 0.26.0 before 0.26.2 DNSSEC Nonexistence Forgery via Wraparound NSEC

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

The DNSSEC validation in the Hickory DNS hickory-net crate 0.26.0 before 0.26.2 identifies wraparound NSEC records by comparing the next domain name to an SOA record in the response, accepting that SOA even if it fails validation. Attackers who can supply DNS responses can combine a genuine NSEC record and its RRSIG with a crafted SOA record to forge nonexistence of any RRset.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- hickory-dns / hickory-dns (hickory-net): ≥ 0.26.0; < 0.26.2 (affected, semver); 0.26.2 (unaffected, semver). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 8.9 (high); CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 6.8 (medium); CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:N; source: CNA: VulnCheck

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-290

## 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-qw83-5pm2-ggp5 (CNA: VulnCheck; vendor-advisory)

- https://www.vulncheck.com/advisories/hickory-dns-0.26.0-before-0.26.2-dnssec-nonexistence-forgery-via-wraparound-nsec (CNA: VulnCheck; third-party-advisory)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-123587; retrieved 2026-11-08; source updated 2026-11-08

Revision: cb2c05dcadacf77ef79f8f9df73b4f76e3eb0b1c020a1cf743d89a870cbce671

Canonical: https://y2.dev/cve/CVE-2026-123587

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