The Paid Membership Subscriptions WordPress plugin before 3.1.0 does not bind one of its unauthenticated payment actions to the requesting user, allowing someone who holds another member's in-flight…

Summary

The Paid Membership Subscriptions WordPress plugin before 3.1.0 does not bind one of its unauthenticated payment actions to the requesting user, allowing someone who holds another member's in-flight payment identifier to delete that member's checkout state.