CVE-2026-77205 (GCVE-0-2026-77205)

Vulnerability from cvelistv5 – Published: 2026-10-13 21:28 – Updated: 2026-10-16 15:31
VLAI
Title
Denial of Service via sending bogus X.509 certificates
Summary
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.
Severity
3.7 (Low)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-16 15:14 UTC
CWE
  • CWE-772 - Missing Release of Resource after Effective Lifetime
Assigner
libreswan CNA under the mitre root
CNA scorecard – unranked: 8 records in the last 180 days, 10 needed details
References
Impacted products
Vendor Product Version CPE status
The Libreswan Project libreswan Affected: 5.3 , ≤ 5.3.2 (semver)
Unaffected: 5.3.3 (semver)
guessed Create a notification for this product.
Credits
Wojciech Tatarski (TuxCare)
Show details on NVD website
To clipboard 

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