CVE-2017-8410

Vulnerability

The vulnerability resides in the rtspd binary located in /sbin on D-Link DCS-1100 and DCS-1130 devices. The binary handles RTSP connections and performs a memcpy operation at address 0x00011E34 using the value sent in the Authorization: Basic RTSP header. The number of bytes copied is calculated from the length of the header string, but no bounds checking is performed, leading to a stack buffer overflow. This overflow corrupts registers in the caller function sub_F6CC and subsequently allows overwriting the stack buffer in function 0x00011378, enabling control of the program counter (PC) register. All firmware versions of these devices are likely affected [1][2].

Exploitation

An attacker can exploit this vulnerability by sending a crafted RTSP request to the device's RTSP port (typically TCP 554) without any prior authentication. The request must include an overly long Authorization: Basic header value. The memcpy copies more data than the stack buffer can hold, corrupting registers and eventually allowing the attacker to overwrite the PC register. No user interaction or special network position is required beyond network access to the device [1][2].

Impact

Successful exploitation results in arbitrary code execution on the device. The attacker gains full control over the affected D-Link DCS-1100 or DCS-1130 camera, likely with root privileges, as the rtspd process runs with elevated permissions. This can lead to complete compromise of the device, including access to video feeds, network pivoting, and potential use in botnets [1][2].

Mitigation

As of the publication date, no official firmware patch has been released by D-Link for this vulnerability. The devices may be end-of-life. Mitigation strategies include disabling the RTSP service if not required, restricting network access to the device via firewall rules, and segmenting IoT devices on a separate VLAN. Users should monitor vendor advisories for any future updates [1][2].