Flaw in Media Library Impacts VLC, Other Software

A serious vulnerability in the LIVE555 Streaming Media RTSP server affects popular applications, including VLC, MPlayer and others, Cisco Talos has discovered.

Developed by Live Networks, Inc, LIVE555 Streaming Media represents a set of open-source C++ libraries meant for multimedia streaming. The libraries provide support for open standards used in streaming, but can also be used for the management of various popular video and audio formats. In addition to media players, the libraries are used for cameras and other embedded devices.

Recently, security researcher Lilith Wyatt of Cisco Talos discovered an exploitable code execution bug in the HTTP packet-parsing functionality of the LIVE555 RTSP server library. An attacker can achieve code execution by sending a specially crafted packet to cause a stack-based buffer overflow.

Tracked as CVE-2018-4013, the vulnerability was found in a function that parses HTTP headers for tunneling RTSP over HTTP. The ability to tunnel RTSP over HTTP, enabled by LIVE555 for the standard RTSP server, is served by a different port bound by the server.

Typically, port TCP 80, 8000, or 8080 is used, based on what is available on the host machine, because the port includes support for normal RTSP. However, it is also possible for the HTTP client to negotiate the RTSP-over-HTTP tunnel.

To exploit the security bug, an attacker could create a packet containing multiple “Accept:” or “x-sessioncookie” strings, thus leading to a stack buffer overflow in the function “lookForHeader.”

The vulnerability, which has a CVSSv3 score of 10.0, has been confirmed to affect Live Networks LIVE555 Media Server version 0.92 (older versions may also be impacted). Live Networks addressed the vulnerability last week.