CVE-2026-123601 json
Hickory DNS 0.26.0-beta.1 before 0.26.2 NSEC3 Proof of Nonexistence Forgery
published 2mo ago modified yesterday also EUVD-2026-119360 , GHSA-588m-chg6-8jqj
Unreviewed: the maintainers' own advisory
Published by the maintainers on their GitHub repository hickory-dns/hickory-dns. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.
- cvss
- 6.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 20%
- public exploits
- 0
- none known
Summary
Hickory DNS hickory-proto 0.25.0 through 0.26.0-alpha.1 and hickory-net 0.26.0-beta.1 before 0.26.2 invert the relational operators in the wrap-around branch of find_covering_record() in nsec3.rs, so the last NSEC3 record in a zone's hash ring covers every hash except its owner. Attackers able to inject DNS responses can replay that NSEC3 record and its RRSIG to forge DNSSEC-validated negative responses denying legitimate names.
Patch / fix
- hickory-dns hickory-dns 0.26.2
- rust-hickory-net Debian 14 0.26.3-1
debian advisories DEBIAN-CVE-2026-123601
Is CVE-2026-123601 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- yesterday
Exploit prediction
0.28% chance of exploitation in the next 30 days, higher than 20% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.3 | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N |
| CNA | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H |
| CNA | 4.0 | 8.3 | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- hickory-dns hickory-dns
Classification
- Weakness
-
- CWE-480 Use of Incorrect Operator
References
-
github.com
/hickory-dns/hickory-dns/security/advisories/GHSA-588m-chg6-8jqj
vendor-advisory, advisory
-
vulncheck.com
/advisories/hickory-dns-0.26.0-beta.1-before-0.26.2-nsec3-proof-of-nonexistence-forgery
third-party-advisory
Sources
- CVE List CVE-2026-123601
- NVD CVE-2026-123601
- Maintainer advisory GHSA-588m-chg6-8jqj
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
The maintainers of hickory-dns/hickory-dns published their own advisory on GitHub. Reviewed sources take precedence over it.