Arcane’s updater service contains a command injection flaw that lets an attacker supply a malicious command via lifecycle labels, which are passed directly to /bin/sh -c without validation. When a container update is performed, the injected command executes inside the target container, enabling arbitrary code execution on the host.

The vulnerability applies to the Arcane Docker management tool from getarcaneapp. Any instance running a version older than 1.13.0 is exposed because lifecycle labels can be set by any authenticated API user. The issue was fixed in Arcane 1.13.0 and later releases.

The CVSS score of 9.1 indicates critical severity, while the EPSS score of 2% reflects a low but non-zero probability of exploitation. The vulnerability is not listed in the CISA KEV catalog. Exploitation requires an authenticated API user to create a project with a malicious lifecycle label, and the compromise occurs when an administrator triggers a container update, at which point the injected command runs inside the container.