Red Hat Security Advisory

RHSA-2026:89923

libreswan security update

Released 2026-10-26 · Red Hat rating Important · View on Red Hat →

Fixed in

Red Hat Enterprise Linux AppStream (v. 10) libreswan-5.3.3-1.el10_2, libreswan-minimal-5.3.3-1.el10_2

Fixes 3 records

TI-2026-73738 CVE-2026-94453 · GHSA-59fc-px6w-3g8v

Use-after-free in Libreswan IKE over TCP handling

LOW 39

Libreswan's pluto daemon has a use-after-free vulnerability when a client connecting using IKE over TCP closes the connection and another packet (retransmit or malicious) is received for the same tuple.

CVSS 3.1HIGH 7.5 Network No auth No interaction EPSS 0.00454 Published 2026-10-13 Partial fix · 5.3.3, 5.4.1 CWE-416

TI-2026-73734 CVE-2026-77207 · GHSA-jf6r-wr9w-j67c

Null pointer dereference in Libreswan PKCS#7 bundle handling

LOW 39

Libreswan has a null pointer dereference bug in the PKCS#7 handling code for IKE certificate authentication.

CVSS 3.1HIGH 7.5 Network No auth No interaction EPSS 0.00463 Published 2026-10-13 Partial fix · 5.3.3, 5.4.1 CWE-252

TI-2026-73732 CVE-2026-77205 · GHSA-7m29-c28j-rg7h

Denial of service via bogus X.509 certificates in Libreswan

LOW 17

Libreswan in FIPS mode has a vulnerability where badly formed received certificates are rejected, but not deleted from the NSS cache.

CVSS 3.1LOW 3.7 Network No auth No interaction EPSS 0.00183 Published 2026-10-13 Partial fix · 5.3.3 CWE-772