The AT&T U-verse 9.2.2h0d83 firmware for the Arris NVG599 device, when IP Passthrough mode is not used, configures WAN access to a caserver https service with the tech account and an empty password, which allows remote attackers to obtain root privileges by establishing a session on port 49955 and then installing new software, such as BusyBox with "nc -l" support.