A remote code execution vulnerability exists in HybridAuth versions 2.0.9 through 2.2.2 due to insecure use of the install.php installation script. The script remains accessible after deployment and fails to sanitize input before writing to the application’s config.php file. An unauthenticated attacker can inject arbitrary PHP code into config.php, which is later executed when the file is loaded. This allows attackers to achieve remote code execution on the server. Exploitation of this issue will overwrite the existing configuration, rendering the application non-functional.