CVE-2026-77205
CVE-2026-77205 · Denial of Service via sending bogus X.509 certificates
This page contains facts from public vulnerability sources. Check the original advisory before updating.
Libreswan in FIPS mode has a vulnerability where badly formed received certificates are rejected, but not deleted from the NSS cache. As a result, any real certificates with the same serial number are rejected as well. This can be abused to lock out legitimate peers from connecting. The add_decoded_cert() function missed a call to CERT_DestroyCertificate() due to an incorrect fix for CVE-2026-14957. Sending bogus certificates with new serial numbers could prevent the real certificates with those serial numbers from connecting until the service has restarted.
CVSS 3.7 · Low · EPSS 0.2%
- Published
- Updated
Stack: system
Affected products and versions
libreswan
- Versions
- ≥ 5.3, ≤ 5.3.2: Affected (semver)
- 5.3.3: Not affected (semver)
No fix published
libreswan Debian:14
- Versions
- 5.2-2.2
- 5.2-2.3
- 5.2-2.4
- 5.2-2.5
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
libreswan Ubuntu:18.04:LTS
- Versions
- 3.20-7build1
- 3.21-2
- 3.22-1
- 3.22-2
- 3.22-3
- 3.22-4
- 3.23-1
- 3.23-4
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
libreswan Ubuntu:20.04:LTS
- Versions
- 3.29-2
- 3.29-2build1
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
libreswan Ubuntu:22.04:LTS
- Versions
- 3.32-3ubuntu3
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
libreswan Ubuntu:24.04:LTS
- Versions
- 4.11-1ubuntu1
- 4.12-1ubuntu1
- 4.14-1ubuntu1
- 4.14-1ubuntu2
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
libreswan Ubuntu:26.10
- Versions
- 5.2-2.2ubuntu2
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
libreswan Ubuntu:26.04:LTS
- Versions
- 5.2-2.2ubuntu1
- 5.2-2.2ubuntu2
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published