Advanced Country Blocker <= 2.3.1 - Unauthenticated Authorization Bypass

Description

The plugin is vulnerable to Authorization Bypass due to the use of a predictable default value for the secret bypass key created during installation without requiring users to change it. This makes it possible for unauthenticated attackers to bypass the geolocation blocking mechanism by appending the key to any URL on sites where the administrator has not changed the default value.