CVE-2026-14957

Name	CVE-2026-14957
Description	In FIPS mode, Libreswan's add_decoded_cert() function calls CERT_ExtractPublicKey() and asserts that the result is not NULL. However, CERT_ExtractPublicKey() returns NULL when public key extraction fails, for example if the RSA exponent is set to 0. A remote attacker can send a malformed X.509 certificate in a CERT payload to trigger the assertion, causing the pluto daemon to abort and restart. Continued exploitation causes a denial of service. No remote code execution is possible. Both IKEv1 and IKEv2 are affected. The vulnerability is only exploitable when both the OS and libreswan are running in FIPS mode and at least one CA certificate is loaded. The CERT payload is processed before peer authentication, so no credentials are needed to exploit this. Configurations using only PreSharedKey (PSK) authentication with no CA certificates loaded in the NSS database are not vulnerable.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
Debian Bugs	1143067

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
libreswan (PTS)	bookworm	4.10-2+deb12u1	vulnerable
	trixie	5.2-2.2	vulnerable
	forky, sid	5.2-2.5	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
libreswan	source	bullseye	(unfixed)	end-of-life
libreswan	source	(unstable)	5.2-2.5			1143067

Notes

[trixie] - libreswan <no-dsa> (Minor issue; can be fixed via point release)
[bullseye] - libreswan <end-of-life> (EOL in bullseye LTS)
https://bugzilla.redhat.com/show_bug.cgi?id=2501764
https://libreswan.org/security/CVE-2026-14957/CVE-2026-14957.txt
Patch: https://libreswan.org/security/CVE-2026-14957/CVE-2026-14957.patch