It was discovered systemd does not correctly check the content of PIDFile
files before using it to kill processes. When a service is run from an
unprivileged user (e.g. User field set in the service file), a local
attacker who is able to write to the PIDFile of the mentioned service may
use this flaw to trick systemd into killing other services and/or
privileged processes. Versions before v237 are vulnerable.
Upstream:released (237-1)
Ubuntu 12.04 ESM (Precise Pangolin):DNE
Ubuntu 14.04 ESM (Trusty Tahr):not-affected (code not built)
Ubuntu 16.04 LTS (Xenial Xerus):needed
Ubuntu 18.04 LTS (Bionic Beaver):not-affected (237-3ubuntu10.9)
Ubuntu 19.04 (Disco Dingo):not-affected
Ubuntu 19.10 (Eoan Ermine):not-affected
Ubuntu 20.04 (Focal Fossa):not-affected
More Information

Updated: 2019-12-05 19:54:30 UTC (commit 0aa5e7c87c8b55d2ec5c7f4ca1179cf75de91961)