The ProfileGrid WordPress plugin before 5.9.9.7 does not verify PayPal IPN notifications before granting paid group membership, allowing unauthenticated attackers to forge a payment notification and mark any user as a paid member of any group without any payment being made.
The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.
Access control involves the use of several protection mechanisms such as:
When any mechanism is not applied or otherwise fails, attackers can compromise the security of the product by gaining privileges, reading sensitive information, executing commands, evading detection, etc. There are two distinct behaviors that can introduce access control weaknesses: