CVE-2026-12505

Name of the Vulnerable Software and Affected Versions cifs-utils (affected versions not specified)

Description A flaw exists in the cifs.upcall helper that fails to securely drop root privileges before performing user information lookups within a user-controlled environment. A local, low-privileged attacker can use a crafted request key payload to trick the root-owned helper into entering a custom namespace containing a malicious Name Service Switch (NSS) module. This forces the system to load the attacker's controlled NSS module and configuration, enabling the execution of arbitrary commands as the root user and resulting in full system compromise.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.