A service component running as root within a WSL instance attaches the instance to Ubuntu Pro by executing the pro client and passing the Ubuntu Pro token as a command-line argument. On systems where `/proc` is mounted without process-hiding mitigations like `hidepid` (the default in WSL), an unprivileged local user or process can read the token from `/proc/<pid>/cmdline` during the attachment process. This leak allows an attacker to use the token to attach other machines to the victim's subscription and gain unauthorized access to Ubuntu Pro services and repositories.