CVE-2026-77205 Affecting libreswan package, versions *


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.18% (8th percentile)

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  • Snyk IDSNYK-ECHOLATEST-LIBRESWAN-20936514
  • published14 Oct 2026
  • disclosed13 Oct 2026

Introduced: 13 Oct 2026

NewCVE-2026-77205  (opens in a new tab)

How to fix?

There is no fixed version for Echo:latest libreswan.

NVD Description

Note: Versions mentioned in the description apply only to the upstream libreswan package and not the libreswan package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

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 Base Scores

version 3.1