An OS command injection vulnerability exists in sar2html version 3.2.2 and prior via the plot parameter in index.php. The application fails to sanitize user-supplied input before using it in a system-level context. Remote, unauthenticated attackers can inject shell commands by appending them to the plot parameter (e.g., ?plot=;id) in a crafted GET request. The output of the command is displayed in the application's interface after interacting with the host selection UI. Successful exploitation leads to arbitrary command execution on the underlying system.