What the vulnerability does
Description
CtrlPanel is open-source billing software for hosting providers. In versions 1.1.1 and prior, the admin settings update endpoint accepted a fully qualified class name directly from user-supplied request input and used it for dynamic static method calls and object instantiation without any allowlist validation, allowing for authenticated Remote Code Execution. An authenticated admin-level user could supply an arbitrary class name available in the Composer autoloader, potentially triggering unintended constructor or magic method execution. The update() method reads settings_class directly from the HTTP request and passed it to new $settings_class() and $settings_class::getValidations() without verifying that the provided value corresponds to a legitimate settings class: Because PHP resolves class names against the Composer autoloader at runtime, any autoloadable class in the application or its dependencies could be instantiated. Depending on the classes available in the dependency tree, this can trigger unintended side effects through constructors or magic methods (__construct, __toString, __wakeup), following a PHP object injection / gadget chain pattern. This issue has been fixed in version 1.2.0.
