This page contains a technical description of the back-door found in Samsung Galaxy devices. For a general description of the issue, please refer to the statement published on the Free Software Foundation's website . This back-door is present in most proprietary Android systems running on the affected Samsung Galaxy devices, including the ones that are shipped with the devices. However, when Replicant is installed on the device, this back-door is not effective: Replicant does not cooperate with back-doors. Abstract Samsung Galaxy devices running proprietary Android versions come with a back-door that provides remote access to the data stored on the device. In particular, the proprietary software that is in charge of handling the communications with the modem, using the Samsung IPC protocol, implements a class of requests known as RFS commands, that allows the modem to perform remote I/O operations on the phone's storage. As the modem is running proprietary software, it is like