AVideo is a video-sharing Platform. Prior to 8.1.0, the unauthenticated installer endpoint install/checkConfiguration.php assembles videos/configuration.php by interpolating request parameters, including webSiteRootURL, into single-quoted PHP string literals without escaping. An attacker can terminate a literal and inject PHP that executes as the web-server user when the generated, directly requestable file is loaded. Exploitation requires videos/configuration.php to be absent, as on every fresh deployment or after the file is removed or moved; an existing file blocks this endpoint. The supplied systemRootPath must contain index.php and a connection using databaseHost, databaseUser, and databasePass must succeed, but the attacker can point those parameters to their own database server and…