Threats Tagged 'cve-2026-16552'

A vulnerability in systemd-tmpfiles allows an unprivileged local user to exploit symbolic link handling when writing files via tmpfiles.d configuration. The flaw arises because a safety check incorrectly treats transitions away from the root user as safe, enabling redirection of privileged writes to arbitrary files. The content written is controlled by the configuration, not the attacker. This vulnerability primarily impacts system integrity.

A flaw was found in systemd-tmpfiles. When processing a tmpfiles.d configuration entry that writes to a file, systemd-tmpfiles can follow a symbolic link placed by an unprivileged local user, and an existing safety check does not detect this specific case because it always treats transitions away from the root user as safe. On systems where a tmpfiles.d configuration targets a path an unprivileged user can influence, this could allow that user to redirect a privileged systemd-tmpfiles write to a file of their choosing, though the content written remains determined by the existing configuration rather than by the unprivileged user. The highest threat from this vulnerability is to integrity.