---
id: CVE-2026-123597
title: Hickory DNS DNSSEC Validation Cache Poisoning via Transient DS-Fetch Errors
summary: >-
  Hickory DNS hickory-proto 0.25.0-alpha.1 through 0.26.0-alpha.1 and
  hickory-net before 0.26.2 contain a logic bug in DnssecDnsHandle's DS-fetch
  path that caches transient DS lookup errors as Bogus DNSSEC validation
  verdicts. An attacker …
severity: low
cvss: 3.7
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L'
cvssSource: cna
cwe:
  - CWE-613
vendor: hickory-dns
product: hickory-dns
affected:
  - hickory-dns >= 0.25.0-alpha.1 <= 0.26.0-alpha.1
  - hickory-dns >= 0.26.0-beta.1 < 0.26.2
published: '2026-11-08'
updated: '2026-11-08'
sourceUpdated: '2026-11-08T01:38:26.431Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-123597'
references:
  - url: >-
      https://github.com/hickory-dns/hickory-dns/security/advisories/GHSA-xv7c-h5g9-x25x
    label: GitHub Security Advisory (GHSA-xv7c-h5g9-x25x)
  - url: >-
      https://www.vulncheck.com/advisories/hickory-dns-dnssec-validation-cache-poisoning-via-transient-ds-fetch-errors
    label: >-
      VulnCheck Advisory: Hickory DNS DNSSEC Validation Cache Poisoning via
      Transient DS-Fetch Errors
tags:
  - cve.org
ingestedAt: '2026-11-08T02:43:18.643Z'
---

## Overview

Hickory DNS hickory-proto 0.25.0-alpha.1 through 0.26.0-alpha.1 and hickory-net before 0.26.2 contain a logic bug in DnssecDnsHandle's DS-fetch path that caches transient DS lookup errors as Bogus DNSSEC validation verdicts. An attacker who induces a SERVFAIL, REFUSED, or timeout response to a child-zone DS sub-query causes the validator to return SERVFAIL for all names under that zone until the cache entry's TTL expires.

## Affected

- `hickory-dns >= 0.25.0-alpha.1 <= 0.26.0-alpha.1`
- `hickory-dns >= 0.26.0-beta.1 < 0.26.2`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.