Linux Distros Unpatched Vulnerability : CVE-2026-91142

low Nessus Plugin ID 348616

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.

- A flaw was found in Cockpit. An integer overflow vulnerability in the `do_lastlog()` function, specifically in the offset calculation for `lastlog` entries on ILP32 (Integer, Long, Pointer 32-bit) builds, can be exploited. A low-privileged authenticated user with a specially provisioned large User ID (UID) can cause the computed offset to wrap around. This allows the user to perform unauthorized reads and writes to other users' `lastlog` records, potentially disclosing or altering sensitive login accounting information. (CVE-2026-91142)

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-2026-91142

https://security-tracker.debian.org/tracker/CVE-2026-91142

https://ubuntu.com/security/CVE-2026-91142

Plugin Details

Severity: Low

ID: 348616

File Name: unpatched_CVE_2026_91142.nasl

Version: 1.3

Type: Local

Agent: unix

Family: Misc.

Published: 9/21/2026

Updated: 9/22/2026

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

Risk Information

VPR

Risk Factor: Low

Score: 2.1

Percentile: 8.04

CVSS v2

Risk Factor: Medium

Base Score: 5.5

Temporal Score: 4.7

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

CVSS Score Source: CVE-2026-91142

CVSS v3

Risk Factor: Low

Base Score: 3.6

Temporal Score: 3.3

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

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:debian:debian_linux:12.0, cpe:/o:debian:debian_linux:13.0, cpe:/o:debian:debian_linux:14.0, cpe:/o:redhat:enterprise_linux:10, cpe:/o:redhat:enterprise_linux:9, p-cpe:/a:canonical:ubuntu_linux:cockpit, p-cpe:/a:debian:debian_linux:cockpit, p-cpe:/a:redhat:enterprise_linux:cockpit-bridge, p-cpe:/a:redhat:enterprise_linux:cockpit-doc, p-cpe:/a:redhat:enterprise_linux:cockpit-packagekit, p-cpe:/a:redhat:enterprise_linux:cockpit-pcp, p-cpe:/a:redhat:enterprise_linux:cockpit-storaged, p-cpe:/a:redhat:enterprise_linux:cockpit-system, p-cpe:/a:redhat:enterprise_linux:cockpit-ws-selinux, p-cpe:/a:redhat:enterprise_linux:cockpit-ws, p-cpe:/a:redhat:enterprise_linux:cockpit

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

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 9/18/2026

Reference Information

CVE: CVE-2026-91142