systemd-tmpfiles in systemd before 237 attempts to support ownership/permission changes on hardlinked files even if the fs.protected_hardlinks sysctl is turned off, which allows local users to bypass intended access restrictions via vectors involving a hard link to a file for which the user lacks write access, as demonstrated by changing the ownership of the /etc/passwd file.
Add your gear to cvedb and we'll alert you only when systemd_project ships something exploited.
Check my exposure →This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.