CVE-2026-44690
CVE-2026-44690 · Cross-zone wildcard cache poisoning via RRSIG.labels manipulation
This page contains facts from public vulnerability sources. Check the original advisory before updating.
In NLnet Labs Unbound 1.7.0 up to and including 1.25.1, insufficient validation of the RRSIG.Labels field combined with premature cache writes during RFC 8198 aggressive NSEC processing leads to cache poisoning that permits a malicious actor controlling a single delegated zone to poison arbitrary sibling zones under NSEC-signed parent domains. A malicious actor with one registered domain under an NSEC-signed TLD can serve malicious insecure DNS responses for unrelated sibling domains (sharing the same parent zone). Arbitrary delegations that do not exist under the parent domain and are covered by the parent's NSEC chain can be brought into insecure existence by fraudulent wildcard DS records (less labels than expected, unknown algorithm) from the malicious sibling domain. This allows the malicious actor to inject insecure wildcard records for those delegations.
CVSS 7.5 · High · EPSS 0.2% · Fix available
- Published
- Updated
Stack: system
Affected products and versions
unbound
- Versions
- ≥ 1.7.0, < 1.25.2: Affected (semver)
Update to 1.25.2
unbound Debian:12
- Versions
- 1.17.1-2
- 1.17.1-2+deb12u1
- 1.17.1-2+deb12u2
- 1.17.1-2+deb12u3
- 1.17.1-2+deb12u4
- 1.17.1-2+loong64
- 1.18.0-1
- 1.18.0-2
- 1.19.1-1
- 1.19.2-1
- 1.20.0-1
- 1.21.1-1
- 1.22.0-1
- 1.22.0-2
- 1.23.1-1
- 1.24.0-1
- 1.24.0-2
- 1.24.1-1
- 1.24.1-2
- 1.24.2-1
- 1.25.0-1
- 1.25.1-1
- 1.25.2-1
- 1.26.0-1
- 1.26.0-2
- 1.26.1-1
- 1.26.2-1
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
unbound Debian:13
- Versions
- 1.22.0-2
- 1.22.0-2+deb13u1
- 1.22.0-2+deb13u2
- 1.22.0-2+deb13u3
- 1.23.1-1
- 1.24.0-1
- 1.24.0-2
- 1.24.1-1
- 1.24.1-2
- 1.24.2-1
- 1.25.0-1
- 1.25.1-1
- 1.25.2-1
- 1.26.0-1
- 1.26.0-2
- Affected ranges
- ECOSYSTEM: < 1.26.1-0+deb13u1
Update to 1.26.1-0+deb13u1
unbound Debian:14
- Versions
- 1.22.0-2
- 1.23.1-1
- 1.24.0-1
- 1.24.0-2
- 1.24.1-1
- 1.24.1-2
- 1.24.2-1
- 1.25.0-1
- 1.25.1-1
- Affected ranges
- ECOSYSTEM: < 1.25.2-1
Update to 1.25.2-1
unbound Ubuntu:Pro:20.04:LTS
- Versions
- 1.9.0-2ubuntu1
- 1.9.0-2ubuntu2
- 1.9.4-2
- 1.9.4-2ubuntu1
- 1.9.4-2ubuntu1.1
- 1.9.4-2ubuntu1.2
- 1.9.4-2ubuntu1.3
- 1.9.4-2ubuntu1.4
- 1.9.4-2ubuntu1.5
- 1.9.4-2ubuntu1.6
- 1.9.4-2ubuntu1.8
- 1.9.4-2ubuntu1.9
- 1.9.4-2ubuntu1.11
- 1.9.4-2ubuntu1.11+esm1
- 1.9.4-2ubuntu1.11+esm2
- Affected ranges
- ECOSYSTEM: < 1.9.4-2ubuntu1.11+esm3
Update to 1.9.4-2ubuntu1.11+esm3
unbound Ubuntu:22.04:LTS
- Versions
- 1.13.1-1ubuntu1
- 1.13.1-1ubuntu3
- 1.13.1-1ubuntu5
- 1.13.1-1ubuntu5.1
- 1.13.1-1ubuntu5.2
- 1.13.1-1ubuntu5.3
- 1.13.1-1ubuntu5.4
- 1.13.1-1ubuntu5.5
- 1.13.1-1ubuntu5.7
- 1.13.1-1ubuntu5.8
- 1.13.1-1ubuntu5.10
- 1.13.1-1ubuntu5.11
- 1.13.1-1ubuntu5.12
- 1.13.1-1ubuntu5.13
- 1.13.1-1ubuntu5.14
- 1.13.1-1ubuntu5.15
- 1.13.1-1ubuntu5.16
- Affected ranges
- ECOSYSTEM: < 1.13.1-1ubuntu5.17
Update to 1.13.1-1ubuntu5.17
unbound Ubuntu:24.04:LTS
- Versions
- 1.17.1-2
- 1.18.0-2ubuntu1
- 1.18.0-2ubuntu2
- 1.19.1-1ubuntu1
- 1.19.2-1ubuntu1
- 1.19.2-1ubuntu3
- 1.19.2-1ubuntu3.1
- 1.19.2-1ubuntu3.2
- 1.19.2-1ubuntu3.3
- 1.19.2-1ubuntu3.4
- 1.19.2-1ubuntu3.5
- 1.19.2-1ubuntu3.6
- 1.19.2-1ubuntu3.7
- 1.19.2-1ubuntu3.8
- 1.19.2-1ubuntu3.9
- 1.19.2-1ubuntu3.10
- Affected ranges
- ECOSYSTEM: < 1.19.2-1ubuntu3.12
Update to 1.19.2-1ubuntu3.12
unbound Ubuntu:26.10
- Versions
- 1.24.2-1ubuntu2
- 1.25.1-1ubuntu1
- 1.25.1-1ubuntu3
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
unbound Ubuntu:26.04:LTS
- Versions
- 1.22.0-2ubuntu2
- 1.22.0-2ubuntu4
- 1.24.2-1ubuntu1
- 1.24.2-1ubuntu2
- 1.24.2-1ubuntu2.1
- 1.24.2-1ubuntu2.2
- 1.24.2-1ubuntu2.3
- Affected ranges
- ECOSYSTEM: < 1.24.2-1ubuntu2.4
Update to 1.24.2-1ubuntu2.4