CVE-2021-3566

Name of the Vulnerable Software and Affected Versions ffmpeg versions prior to 4.3

Description The issue is related to the tty demuxer in the FFmpeg library, which did not have a read probe function assigned to it. This can be exploited by crafting a legitimate "ffconcat" file that references an image, followed by a file that triggers the tty demuxer. As a result, the contents of the second file will be copied into the output file verbatim, provided the -vcodec copy option is passed to ffmpeg. This could allow a remote attacker to access confidential data.

Recommendations For versions prior to 4.3, update to version 4.3 or later to resolve the issue. As a temporary workaround, consider avoiding the use of the -vcodec copy option with the tty demuxer until a patch is applied. Additionally, restrict the use of specially crafted "ffconcat" files to minimize the risk of exploitation.