boneIO black_debian_images gives the boneio service account excessive privileges, including full passwordless sudo access and membership in the docker group. A local attacker who compromises the boneio user can use these privileges to escalate to root.
This issue was fixed in version 1.6.0: the image removes the sudoers rule and the docker group membership when it is sealed, and devices already in the field have both removed by migrations shipped with boneio 1.6.0 and applied on first start after the upgrade. Privileged operations now go through helpers that accept only a fixed set of commands, with migrations verified against Ed25519 signatures.