# CVE-2026-123605: Hickory DNS through 0.25.0-alpha.3 DNSSEC Validation Bypass via RRSIG Signer's Name

CVE-2026-123605 is fixed in rust-hickory-net on 1 platform by DEBIAN-CVE-2026-123605 (version 0.26.3-1), released November 9, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-123605
- Priority: High
- CVSS: 8.8 (Important)
- EPSS: 0.0024
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Nov 8, 2026
- Weakness: Improper Verification of Cryptographic Signature
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-123605

## Description

Hickory DNS hickory-proto 0.1 through 0.25.0-alpha.3 and hickory-net before 0.26.2 contain a DNSSEC validation bypass because the validator verifies an RRSIG against the DNSKEY of whatever name appears in its Signer's Name field without checking that this name is the zone containing the RRset. Attackers controlling any secure zone can produce valid signatures over arbitrary records in unrelated zones, which resolvers, recursors, and clients using DnssecDnsHandle accept as authenticated.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | rust-hickory-net Debian 14 | 0.26.3-1 | [DEBIAN-CVE-2026-123605](https://patchblox.com/security/data/fix/linux/debian-cve-2026-123605.md) | Nov 9, 2026 |

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Data as of 2026-11-11T13:47:35Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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