WeGIA: Pre-auth Installer Injection Chain Enables Command Execution and Arbitrary PHP Code Injection

WeGIA is a web manager for charitable institutions. Prior to 3.8.6, the pre-installation web/instalador/instalador.php endpoint is reachable before config.php exists and processes unauthenticated installation POST data. In the Linux reinstall flow, a crafted usuario value reaches a command executed by shell_exec(). The installer also writes attacker-controlled values into executable config.php and concatenates the database name nomebd into a CREATE DATABASE statement. Successful exploitation can execute commands as the web-server user, persist attacker-controlled PHP configuration, and alter or disrupt the application and its data. This issue is fixed in version 3.8.6.