CVE-2019-9718 : Security Advisory and Response

FFmpeg versions 3.2 and 4.1 have a vulnerability in the subtitle decoder that can be exploited by attackers to consume excessive CPU resources by using a specifically designed video file in the Matroska format. The vulnerability lies in the ff_htmlmarkup_to_ass function in libavcodec/htmlsubtitles.c.

Understanding CVE-2019-9718

This CVE entry highlights a denial of service vulnerability in FFmpeg versions 3.2 and 4.1.

What is CVE-2019-9718?

CVE-2019-9718 is a vulnerability in FFmpeg versions 3.2 and 4.1 that allows attackers to hog the CPU by using a crafted video file in Matroska format.

The Impact of CVE-2019-9718

Attackers can exploit this vulnerability to cause denial of service by consuming excessive CPU resources.

Technical Details of CVE-2019-9718

This section provides technical details of the vulnerability.

Vulnerability Description

The vulnerability in FFmpeg versions 3.2 and 4.1 allows attackers to hog the CPU via a crafted video file in Matroska format due to a complex format argument in the ff_htmlmarkup_to_ass function.

Affected Systems and Versions

FFmpeg versions 3.2 and 4.1 are affected by this vulnerability.

Exploitation Mechanism

Attackers can exploit this vulnerability by using a specially designed video file in the Matroska format to trigger the issue.

Mitigation and Prevention

Protecting systems from CVE-2019-9718 requires immediate actions and long-term security practices.

Immediate Steps to Take

Update FFmpeg to a patched version that addresses the vulnerability.
Avoid opening video files from untrusted sources.

Long-Term Security Practices

Regularly update software and apply security patches promptly.
Implement network segmentation to limit the impact of potential attacks.

Patching and Updates

Stay informed about security advisories and updates from FFmpeg to patch vulnerabilities promptly.