A flaw was found in Podman. An attacker can trigger a Denial of Service (DoS) by supplying a container image containing crafted metadata labels. Podman's auto-update mechanism improperly trusts these image labels to determine which system services to restart. If a user runs the malicious container and auto-update processes it, arbitrary system services are restarted with the user's privileges, potentially allowing an attacker to shut down the host system when Podman runs with administrative privileges.
Do not use podman auto-update on untrusted containers or images. Before running an image, inspect its labels with podman image inspect --format '.Config.Labels' and verify that the io.containers.autoupdate and PODMAN_SYSTEMD_UNIT labels are not set. For existing containers, inspect their labels and ensure that auto-update labels are configured correctly and only present on containers intended to use auto-update.