Security Flaw in util-linux su Utility Affects Multiple Ubuntu Releases

A security vulnerability has been identified in the util-linux package, specifically affecting the su utility across several Ubuntu releases, including 25.10, 24.04 LTS, 22.04 LTS, and 20.04 LTS. The issue arises from the su utility not dropping capabilities when used with the --pty option, which could allow a local attacker to exploit vulnerabilities in other applications. Although this flaw is not a direct security threat, it opens the door for potential exploitation. Users are advised to update their systems to the latest package versions to mitigate any risks. The affected package versions are 2.41-4ubuntu4.2 for Ubuntu 25.10, 2.39.3-9ubuntu6.5 for 24.04 LTS, 2.37.2-4ubuntu3.5 for 22.04 LTS, and 2.34-0.1ubuntu9.6+esm1 for 20.04 LTS. A standard system update will apply the necessary changes. The vulnerability highlights the importance of maintaining updated software to prevent exploitation.

Key Points: • The util-linux su utility vulnerability affects multiple Ubuntu versions. • Local attackers could exploit this flaw to gain unauthorized access to applications. • Users should update to the latest package versions to mitigate risks.