Linux Distros Unpatched Vulnerability : CVE-2026-12391

medium Nessus Plugin ID 327457

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.

- An insecure symlink following vulnerability exists in Canonical ubuntu-pro-client (formerly ubuntu- advantage-tools) within the pro collect-logs command framework. The utility creates or utilizes predictable temporary file paths or user-accessible log directories when gathering diagnostic information without verifying the file type or ownership. An unprivileged local attacker can exploit this behavior by creating a symbolic link (symlink) at a predictable destination path pointing to an arbitrary, root- readable file (such as /etc/shadow or private files within /root). When a root administrator or operator subsequently executes the pro collect-logs command, the tool follows the user-controlled symlink, reads the target file, and compresses its contents into the resulting diagnostic support archive. Because the output archive remains readable by the unprivileged user, the attacker can extract and read the sensitive root-owned files, leading to a complete information disclosure of system secrets. (CVE-2026-12391)

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://ubuntu.com/security/CVE-2026-12391

Plugin Details

Severity: Medium

ID: 327457

File Name: unpatched_CVE_2026_12391.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Misc.

Published: 7/16/2026

Updated: 7/16/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

CVSS v2

Risk Factor: Medium

Base Score: 6.6

Temporal Score: 5.6

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

CVSS Score Source: CVE-2026-12391

CVSS v3

Risk Factor: Medium

Base Score: 5

Temporal Score: 4.6

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

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

Vulnerability Information

CPE: p-cpe:/a:canonical:ubuntu_linux:ubuntu-advantage-tools, cpe:/o:canonical:ubuntu_linux:25.10

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: 7/16/2026

Reference Information

CVE: CVE-2026-12391