CVE-2021-36692 : Vulnerability Insights and Analysis

libjxl v0.3.7 is affected by a Divide By Zero in issue in lib/extras/codec_apng.cc jxl::DecodeImageAPNG(). When encoding a malicious APNG file using cjxl, an attacker can trigger a denial of service.

Understanding CVE-2021-36692

This CVE highlights a vulnerability in the libjxl library version 0.3.7 that can be exploited to cause a denial of service attack.

What is CVE-2021-36692?

CVE-2021-36692 is a Divide By Zero vulnerability in libjxl v0.3.7, specifically in the jxl::DecodeImageAPNG() function. It can be triggered by an attacker when encoding a malicious APNG file using cjxl.

The Impact of CVE-2021-36692

Exploiting this vulnerability can result in a denial of service condition, affecting the availability of systems utilizing the vulnerable library.

Technical Details of CVE-2021-36692

This section provides insights into the specifics of the CVE.

Vulnerability Description

The vulnerability arises from a Divide By Zero issue in the lib/extras/codec_apng.cc file within the libjxl library version 0.3.7, precisely in the jxl::DecodeImageAPNG() function.

Affected Systems and Versions

The affected version is libjxl v0.3.7. Systems utilizing this specific version are vulnerable to exploitation.

Exploitation Mechanism

An attacker can exploit CVE-2021-36692 by crafting a malicious APNG file and encoding it using cjxl. This can lead to triggering the Divide By Zero issue and subsequently causing a denial of service.

Mitigation and Prevention

Protecting systems from CVE-2021-36692 requires immediate actions and continued security practices.

Immediate Steps to Take

Update to a patched version of libjxl that addresses the Divide By Zero vulnerability.
Monitor for any suspicious activities indicating exploitation of the vulnerability.

Long-Term Security Practices

Regularly update software libraries and dependencies to mitigate known vulnerabilities.
Conduct security assessments and code reviews to identify and address potential weaknesses.
Implement proper input validation and error handling mechanisms in software development practices.

Patching and Updates

Stay informed about security advisories related to libjxl and promptly apply patches or updates to ensure the continued security of your systems.