Lack or insufficent input validation in WebGUI CLI web in Infinera G42 version R6.1.3 allows remote authenticated users to read all OS files via crafted CLI commands. Details: The web interface based management of the Infinera G42 appliance enables the feature of executing a restricted set of commands. This feature also offers the option to execute a script-file already present on the target device. When a non-script or incorrect file is specified, the content of the file is shown along with an error message. Due to an execution of the http service with a privileged user all files on the file system can be viewed this way.