CVE catalog
CVE-2026-77205
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
- Severity
- Low · CVSS 3.7
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L - Published
- Updated
- Source
- [NVD] · [CVE record]
- EPSS
- 0.18% · Oct 25, 2026
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.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | libreswan | sid | 5.2-2.5 | vulnerable |
| Debian | libreswan | forky | 5.2-2.5 | vulnerable |
| Debian | libreswan | trixie | 5.2-2.2 | not affected |
| Debian | libreswan | bookworm | 4.10-2+deb12u1 | not affected |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | libreswan | source | sid | (unfixed) | not yet assigned | Not reported | [1150899] |
| Debian | libreswan | source | forky | (unfixed) | not yet assigned | Not reported | [1150899] |
| Debian | libreswan | source | trixie | Not affected | unimportant | Not reported | [1150899] |
| Debian | libreswan | source | bookworm | Not affected | unimportant | Not reported | [1150899] |
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [libreswan]Not affected
Details (2)
4.10-2+deb12u1· amd64 · bookwormNot affected
nvd · libreswan · debian · bookworm
4.10-2+deb12u1· arm64 · bookwormNot affected
nvd · libreswan · debian · bookworm
Observed:
References
- [https://nvd.nist.gov/vuln/detail/CVE-2026-77205]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-77205]
- [https://security-tracker.debian.org/tracker/CVE-2026-77205]
- [https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-77205.json]
[Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX]