CVE-2022-4120

El complemento Stop Spammers Security | Block Spam Users, Comments, Forms de WordPress anterior a 2022.6 pasa la entrada del usuario codificada en base64 a la función PHP unserialize() cuando se usa CAPTCHA como segundo desafío, lo que podría llevar a la inyección de objetos PHP si un complemento instalado en el blog tiene una cadena de gadgets adecuada

The Stop Spammers Security plugin for WordPress is vulnerable to PHP Object Injection in versions up to, and including, 2022.5 via deserialization of untrusted input when issuing a CPATCHA challenge. This allows unauthenticated attackers to inject a PHP Object. No POP chain is present in the vulnerable plugin. If a POP chain is present via an additional plugin or theme installed on the target system, it could allow the attacker to delete arbitrary files, retrieve sensitive data, or execute code. Note: The official PHP recommendation is not to pass untrusted input to unserialize even if the allowed_classes option is set to false.