CVE-2021-3566 Explained : Impact and Mitigation

A detailed overview of CVE-2021-3566, a vulnerability in ffmpeg version 4.3 that could lead to arbitrary code execution.

Understanding CVE-2021-3566

This section will cover what CVE-2021-3566 is and its impact, technical details, as well as mitigation and prevention strategies.

What is CVE-2021-3566?

Prior to ffmpeg version 4.3, the tty demuxer lacked a 'read_probe' function. Crafted ffconcat files could allow malicious second file content to be copied verbatim with

-vcodec copy

option.

The Impact of CVE-2021-3566

Exploiting this vulnerability could result in an attacker executing arbitrary code on the target system, leading to potential system compromise.

Technical Details of CVE-2021-3566

Get insights into the vulnerability description, affected systems and versions, and the exploitation mechanism.

Vulnerability Description

CVE-2021-3566 arises from tty demuxer's missing 'read_probe' function in ffmpeg version 4.3, enabling content to be copied into an output file.

Affected Systems and Versions

The vulnerability affects ffmpeg version 4.3.

Exploitation Mechanism

Crafted ffconcat files that reference an image, followed by a triggering file for the tty demuxer, can lead to arbitrary code execution.

Mitigation and Prevention

Explore the immediate steps to take and long-term security practices to mitigate risks associated with CVE-2021-3566.

Immediate Steps to Take

Users should update ffmpeg to version 4.3 or later and avoid processing untrusted multimedia files to prevent exploitation.

Long-Term Security Practices

Implement secure coding practices, conduct regular security audits, and stay informed about security updates and patches.

Patching and Updates

Stay vigilant for security advisories, apply patches promptly, and monitor for any unusual file processing activities.