Advanced Custom Fields: Extended < 0.9.2.2 - Unauthenticated Privilege Escalation

Description

The plugin is vulnerable to Privilege Escalation due to the 'insert_user' function not restricting the roles with which a user can register. This makes it possible for unauthenticated attackers to supply the 'administrator' role during registration and gain administrator access to the site. Note: The vulnerability can only be exploited if 'role' is mapped to the custom field.