AI Engine 3.3.3 - 3.7.1 - Subscriber+ Arbitrary File Read via 'url' Parameter

The AI Engine WordPress plugin before 3.7.2 does not confine a caller-supplied URL when mapping it to a local filesystem path before reading the file and forwarding its contents to an external service, allowing users with a subscriber-level account to read arbitrary files from the server and exfiltrate them off-host. Reaching the issue at subscriber level requires a non-default public API feature to be enabled; otherwise the same issue is reachable by an administrator, which on multisite allows a non-super subsite administrator to read the network-shared configuration and its secrets.