DNSSEC validation bypass in Hickory DNS via name hash collision
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- Present
- Impact type
- —
- Confidentiality · integrity · availability
- None · High · None
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
Summary
The hickory-net crate in Hickory DNS from 0.26.0-beta.1 before 0.26.2 has a DNSSEC validation bypass. Name hashing ignores label lengths, and the validation cache compares only that hash, which is a wrong comparison (CWE-1025). A remote attacker who controls an unsigned delegation can cause forged answers for a signed target name to skip signature verification instead of failing.
Written with Claude Haiku 5.5 from the sources below · 2026-11-08
Description from the CNA
The hickory-net crate in Hickory DNS 0.26.0-beta.1 before 0.26.2 allows DNSSEC validation bypass because Name's Hash ignores label lengths and ValidationCacheKey compares only that hash. An attacker controlling an unsigned delegation whose name differs from a signed target only in dot positions can prime an Insecure verdict, causing forged answers for the target to skip signature verification instead of returning SERVFAIL.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| hickory-dns | hickory-dns | 0.26.0-beta.1 to before 0.26.2 | 0.26.2 | Patch available | CNA |
- hickory-dns Vendorhickory-dns Affected 0.26.0-beta.1 to before 0.26.2 Fixed in 0.26.2 Patch available CNA
Remediation
Upgrade Hickory DNS to version 0.26.2, which fixes hickory-dns from 0.26.0-beta.1 before 0.26.2.
Written with Claude Haiku 5.5 from the sources below · 2026-11-08
- Fix · CNA hickory-dns (hickory-dns) Fixed in 0.26.2
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
hickory-dns 0.26.2
36 records Highest priority Priority MEDIUM 36 MEDIUM
Other records, highest priority first
- TI-2026-86729 DNSSEC nonexistence forgery in Hickory DNS via wraparound NSECPriority MEDIUM 54
- TI-2026-86748 Resource exhaustion in hickory-dns recursor via glueless NS referralsPriority MEDIUM 53
- TI-2026-86747 DNSSEC validation bypass in Hickory DNS via RRSIG signer namePriority MEDIUM 53
Timeline
- 2026-11-08 Threatist record created from CVE-2026-123592
- 2026-11-08 Alias added: GHSA-h794-62hf-9phh
References
More hickory-dns vulnerabilities
- TI-2025-18857 DNSSEC validation may accept broken authentication chains CVSS 4.0MEDIUM 5.7
- TI-2026-86729 DNSSEC nonexistence forgery in Hickory DNS via wraparound NSEC CVSS 4.0HIGH 8.9
- TI-2026-86750 CPU exhaustion in Hickory DNS hickory-proto via BinEncoder name compression CVSS 4.0HIGH 8.7
- TI-2026-86749 Hickory DNS NSEC3 validation loop enables denial of service CVSS 4.0HIGH 8.7
- TI-2026-86748 Resource exhaustion in hickory-dns recursor via glueless NS referrals CVSS 4.0HIGH 8.7
- TI-2026-86747 DNSSEC validation bypass in Hickory DNS via RRSIG signer name CVSS 4.0HIGH 8.7
Sources
- CVE-2026-123592 · CVE Program
- CVE-2026-123592 · NVD
- GHSA-h794-62hf-9phh · GitHub Advisory Database · CC BY 4.0
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