Search Regex 3.5 - Authenticated (Subscriber+) Remote Code Execution via User Meta Serialized String Corruption

The Search Regex plugin for WordPress is vulnerable to PHP Object Injection in version 3.5 via deserialization of untrusted input in the replace_all function. This allows authenticated attackers, with subscriber-level access and above, to inject a PHP Object. The additional presence of a POP chain allows attackers to execute code.