CVE-2019-9720 : What You Need to Know

A vulnerability was discovered in Libav 12.3 that could lead to a stack-based buffer overflow in the subtitle decoder when processing a specially crafted video file in Matroska format. The misuse of the snprintf function in the srt_to_ass function allows attackers to manipulate the stack and potentially execute arbitrary code.

Understanding CVE-2019-9720

This CVE identifies a stack-based buffer overflow vulnerability in Libav 12.3 that can be exploited through a specially crafted Matroska video file.

What is CVE-2019-9720?

The vulnerability in Libav 12.3 allows attackers to corrupt the stack by exploiting the subtitle decoder when processing malicious Matroska video files.

The Impact of CVE-2019-9720

The vulnerability enables attackers to potentially execute arbitrary code by manipulating the stack through the subtitle decoder in Libav 12.3.

Technical Details of CVE-2019-9720

This section provides technical details about the vulnerability.

Vulnerability Description

The vulnerability in Libav 12.3 results from a stack-based buffer overflow in the subtitle decoder due to the misuse of the snprintf function in the srt_to_ass function.

Affected Systems and Versions

Affected Version: Libav 12.3
Systems Processing Matroska Video Files

Exploitation Mechanism

Attackers exploit the vulnerability by crafting malicious Matroska video files to trigger the stack-based buffer overflow.

Mitigation and Prevention

Protecting systems from CVE-2019-9720 requires immediate actions and long-term security practices.

Immediate Steps to Take

Update Libav to a patched version that addresses the stack-based buffer overflow.
Avoid opening video files from untrusted sources.

Long-Term Security Practices

Regularly update software and libraries to prevent known vulnerabilities.
Implement code reviews and security testing to identify and address similar issues.

Patching and Updates

Apply patches provided by Libav to fix the vulnerability and prevent exploitation.