CVE-2020-27756 Explained : Impact and Mitigation

CVE-2020-27756, assigned by Red Hat, addresses a vulnerability in ImageMagick that could lead to divide-by-zero conditions and undefined behavior.

Understanding CVE-2020-27756

This CVE involves a flaw in ParseMetaGeometry() of MagickCore/geometry.c in ImageMagick versions prior to 7.0.9-0.

What is CVE-2020-27756?

The vulnerability in ImageMagick's image height and width calculations can result in divide-by-zero conditions, potentially impacting application availability.

The Impact of CVE-2020-27756

The vulnerability could allow an attacker to exploit crafted input files, leading to application unavailability and potential security risks.

Technical Details of CVE-2020-27756

This section provides more technical insights into the vulnerability.

Vulnerability Description

The flaw in ParseMetaGeometry() can trigger divide-by-zero conditions due to incorrect height and width calculations, resulting in undefined behavior.

Affected Systems and Versions

Vendor: n/a
Product: ImageMagick
Affected Versions: prior to 7.0.9-0

Exploitation Mechanism

Crafted input files processed by ImageMagick can exploit this vulnerability, potentially causing application availability issues.

Mitigation and Prevention

To address CVE-2020-27756, follow these mitigation steps:

Immediate Steps to Take

Apply the provided patch that uses multiplication and

PerceptibleReciprocal()

function to prevent divide-by-zero conditions.

Long-Term Security Practices

Regularly update ImageMagick to the latest version to mitigate known vulnerabilities.
Implement input validation mechanisms to prevent the processing of malicious files.

Patching and Updates

Ensure timely patching and updates for ImageMagick to address security vulnerabilities.