Execution with Unnecessary Privileges Affecting cifs-utils package, versions <2:7.4-1ubuntu0.26.04.3


Severity

Recommended
medium

Based on Ubuntu security rating.

Threat Intelligence

EPSS
0.12% (3rd percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-UBUNTU2604-CIFSUTILS-17376366
  • published3 Jul 2026
  • disclosed18 Jun 2026

Introduced: 18 Jun 2026

CVE-2026-12505  (opens in a new tab)
CWE-250  (opens in a new tab)

How to fix?

Upgrade Ubuntu:26.04 cifs-utils to version 2:7.4-1ubuntu0.26.04.3 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream cifs-utils package and not the cifs-utils package as distributed by Ubuntu. See How to fix? for Ubuntu:26.04 relevant fixed versions and status.

A flaw was found in the cifs-utils package where the cifs.upcall helper fails to securely drop its root privileges before looking up user information inside a user-controlled environment. A local, low privileged attacker can exploit this by using a crafted request_key payload to trick the root-owned helper into entering a custom environment (namespace) containing a malicious NSS module. This forces the system to load the attacker's controlled NSS Module and configuration, allowing them to execute arbitrary commands as the root user, elevating their privileges and fully compromising the system.

CVSS Base Scores

version 3.1