Linux Distros Unpatched Vulnerability : CVE-2026-14957

high Nessus Plugin ID 327686

Synopsis

The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be patched.

Description

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

- 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. (CVE-2026-14957)

Note that Nessus relies on the presence of the package as reported by the vendor.

Solution

There is no known solution at this time.

See Also

https://access.redhat.com/security/cve/cve-2026-14957

https://security-tracker.debian.org/tracker/CVE-2026-14957

https://ubuntu.com/security/CVE-2026-14957

Plugin Details

Severity: High

ID: 327686

File Name: unpatched_CVE_2026_14957.nasl

Version: 1.7

Type: Local

Agent: unix

Family: Misc.

Published: 7/18/2026

Updated: 9/2/2026

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.68

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 4.3

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P

CVSS Score Source: CVE-2026-14957

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.9

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:U/RC:C

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:18.04:-:lts, cpe:/o:canonical:ubuntu_linux:20.04:-:lts, cpe:/o:canonical:ubuntu_linux:22.04:-:lts, cpe:/o:canonical:ubuntu_linux:24.04:-:lts, cpe:/o:canonical:ubuntu_linux:26.04:-:lts, cpe:/o:centos:centos:7, cpe:/o:debian:debian_linux:12.0, cpe:/o:debian:debian_linux:13.0, cpe:/o:redhat:enterprise_linux:7, p-cpe:/a:canonical:ubuntu_linux:libreswan, p-cpe:/a:centos:centos:libreswan, p-cpe:/a:debian:debian_linux:libreswan, p-cpe:/a:redhat:enterprise_linux:libreswan

Required KB Items: Host/local_checks_enabled, Host/cpu, global_settings/vendor_unpatched, Host/OS/identifier

Exploit Ease: No known exploits are available

Reference Information

CVE: CVE-2026-14957