dorequest in request.c in muhttpd before 1.1.7 allows remote attackers to read arbitrary files by constructing a URL with a single character before a desired path on the filesystem. This occurs because the code skips over the first character when serving files. Arris NVG443, NVG599, NVG589, and NVG510 devices and Arris-derived BGW210 and BGW320 devices are affected.
The AT&T U-verse 9.2.2h0d83 firmware for the Arris NVG589 and NVG599 devices, when IP Passthrough mode is not used, configures an unauthenticated proxy service on WAN TCP port 49152, which allows remote attackers to establish arbitrary TCP connections to intranet hosts by sending \x2a\xce\x01 followed by other predictable values.
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.
The AT&T U-verse 9.2.2h0d83 firmware for the Arris NVG589 and NVG599 devices, when IP Passthrough mode is not used, configures ssh-permanent-enable WAN SSH logins to the remotessh account with the 5SaP9I26 password, which allows remote attackers to access a "Terminal shell v1.0" service, and subsequently obtain unrestricted root privileges, by establishing an SSH session and then entering certain shell metacharacters and BusyBox commands.
The AT&T U-verse 9.2.2h0d83 firmware for the Arris NVG589, NVG599, and unspecified other devices, when IP Passthrough mode is not used, configures an sbdc.ha WAN TCP service on port 61001 with the bdctest account and the bdctest password, which allows remote attackers to obtain sensitive information (such as the Wi-Fi password) by leveraging knowledge of a hardware identifier, related to the Bulk Data Collection (BDC) mechanism defined in Broadband Forum technical reports.