CVE-2021-3498

Vulnerability

A heap corruption vulnerability exists in the Matroska demuxer of GStreamer's gst-plugins-good library, affecting versions 1.x up to and including 1.18.3 [2][4]. The bug is triggered when parsing specially crafted malformed Matroska media files, leading to memory corruption.

Exploitation

An attacker can exploit this vulnerability by crafting a malicious Matroska file and delivering it to a target user. No authentication is required; the user must open the file with an application that uses GStreamer (e.g., a media player). The parsing of the malformed data causes heap corruption, which may be leveraged for code execution.

Impact

Successful exploitation could result in a denial of service (application crash) or, potentially, arbitrary code execution with the privileges of the user running the vulnerable application [4]. The impact is limited to the user's context.

Mitigation

The issue is fixed in GStreamer gst-plugins-good version 1.18.4 [4]. Users should upgrade to this version or later. Gentoo users can update to >=media-libs/gst-plugins-good-1.20.2 [3]. A patch is available from the GStreamer project [4]. No workaround is known.