What the vulnerability does
01Description
The Contact Form Plugin by Fluent Forms for Quiz, Survey, and Drag & Drop WP Form Builder plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 5.1.15 via deserialization of untrusted input in the extractDynamicValues function. This makes it possible for authenticated attackers, with contributor-level access and above, to inject a PHP Object. 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. Successful exploitation requires the attacker to have "View Form" and "Manage Form" permissions, which must be explicitly set by an administrator. However, this requirement can be bypassed when this vulnerability is chained with CVE-2024-2771.
Explanation of Vulnerability in Simple Terms
02Summary
Fluent Forms versions up to 5.1.15 contain a deserialization vulnerability that allows authenticated attackers to execute arbitrary code on the site. The vulnerability exists in how the plugin processes untrusted serialized data without proper validation. An attacker with low-level access can craft malicious input to trigger code execution with full site privileges.
What an attacker can do
03Attacker Capabilities
Run their own PHP code on the site with full administrative privileges.
Potential impact on your site
04Site Impact
Complete site compromise: attackers can modify content, steal data, install backdoors, or take the site offline.
Conditions required to exploit
05Prerequisites
Attacker must have a low-level user account (subscriber or above) on the WordPress site.
Key dates
06Disclosure timeline
May 22, 2024
CVE published
April 8, 2026
Record updated
