Popup Builder < 3.0 - SQL injection via PHP Deserialization

Description

The Popup Builder plugin 2.2.8 through 2.6.7.6 for WordPress is vulnerable to SQL injection via PHP Deserialization on attacker-controlled data with the attachmentUrl POST variable. This allows creation of an arbitrary WordPress Administrator account, leading to possible Remote Code Execution because Administrators can run PHP code on WordPress instances.

This issue has been fixed in the 3.x branch of popup-builder. Versions 2.2.8 through 2.5.3 do not need a nonce, however 2.5.4 through 2.6.7.6 would need a valid nonce.