Idle locking function in MacOS 9 allows local attackers to bypass the password protection of idled sessions via the programmer's switch or CMD-PWR keyboard sequence, which brings up a debugger that the attacker can use to disable the lock.

Idle locking function in MacOS 9 allows local users to bypass the password protection of idled sessions by selecting the "Log Out" option and selecting a "Cancel" option in the dialog box for an application that attempts to verify that the user wants to log out, which returns the attacker into the locked session.