The vulnerability arises from a project restriction bypass that permits users of restricted projects to exploit block.create_options during volume update, copy, or move operations. This flaw allows injection of custom arguments into the mkfs command, which the system subsequently executes with root privileges. As a result, an attacker can run arbitrary commands in the host environment, leading to a full compromise. The weakness corresponds to CWE‑88, which involves permission checks failing to enforce adequately restricted access outside the normal flow. The likely attack vector is a restricted project user performing a volume copy or move operation that includes malicious block.create_options.

Affected systems include the Incus container runtime from version 7.3.0 up to, but not including, 7.5.0. All builds in this range issued by the Linux Containers project carry the flaw. Anyone deploying any of these releases is susceptible regardless of the host's operating system, as the vulnerability resides in the Incus daemon. No patches for 7.3.0–7.4.x exist until the 7.5.0 update.

The CVSS score of 9 indicates critical severity. EPSS is not available, so the current exploitation probability is unknown, but the vulnerability was publicly disclosed and no research shows widespread exploitation yet. It is not listed in the CISA KEV catalogue. Nevertheless, because the attack requires only an account with restricted project permissions—commonly granted for day‑to‑day operations—the threat surface is broad. Once the malicious block.create_options are committed, the resulting mkfs runs as root, giving the attacker full system privileges. This combination of a high severity score, broad attack surface, and potential for full system compromise makes immediate remediation essential.