CVE-2026-14957: high-severity vulnerability in The Libreswan Project libreswan
FIPS mode assertion failure via malicious CERT payload
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.5epss 0.5%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
The Libreswan Project · libreswanRelated CVEs — The Libreswan Project libreswan
In the same product, most dangerous first.
CVE-2026-77206HIGHIKEv2 pre-authentication Null Pointer Dereference in EAP codeEPSS 0.7%CVE-2026-12413HIGHIKEv2 Denial of Service via malformed fragmentationEPSS 0.6%CVE-2026-77207HIGHNull Pointer Dereference in PKCS#7 bundle with no certificatesEPSS 0.5%CVE-2026-94453HIGHIKEv2 Use-After-Free bug when using IKE-over-TCPEPSS 0.5%CVE-2026-50721HIGHIKEv1 Denial of Service via RSA-SHA1 (PKCS#1 Version 1.5 Encrypted) authentication payloadEPSS 0.4%CVE-2026-50722HIGHIKEv2 Denial of Service via RSA-SHA1 (PKCS#1 RSASSA-PKCS1-v1_5) authentication payloadEPSS 0.3%