CVE-2026-77205
Denial of Service via sending bogus X.509 certificates
LOW 3.7
At a glance
- Source
- NVD
- EPSS
- EPSS 0.18 % · percentile 8 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- libreswan
- NVD status
- Awaiting Analysis
Description
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.
Weaknesses (CWE)
- CWE-772 — Missing Release of Resource after Effective Lifetime
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | LOW 3.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L | libreswan |
| CVSS 3.1 | LOW 3.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L | NVD · d42dc95b-23f1-4e06-9076-20753a0fb0df (Secondary) |
European references
- ENISA EUVD · EUVD-2026-100747
- GCVE · GCVE-0-2026-77205
Affected products
| Product | Versions |
|---|---|
| The Libreswan Project · libreswan | affected 5.3 ≤ 5.3.2 ; unaffected 5.3.3 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |