CVE-2021-37863 : Security Advisory and Response

This article provides an overview of CVE-2021-37863, a vulnerability in Mattermost 6.0 and earlier versions that enables authenticated attackers to cause a client-side crash of the web application by exploiting insufficient parameter validation during post creation.

Understanding CVE-2021-37863

In this section, we will delve into the details of the CVE-2021-37863 vulnerability.

What is CVE-2021-37863?

CVE-2021-37863 pertains to Mattermost versions 6.0 and below, where a lack of proper parameter validation during post creation gives authenticated attackers the ability to trigger a client-side crash through a specially crafted post.

The Impact of CVE-2021-37863

The vulnerability carries a low severity rating with a CVSS base score of 3.5, allowing attackers to exploit it with low privileges and network access. While the impact is limited to causing a client-side crash, it poses a risk to the availability of the web application.

Technical Details of CVE-2021-37863

This section covers the technical aspects of CVE-2021-37863.

Vulnerability Description

Mattermost 6.0 and earlier lack proper validation of parameters during post creation, leading to a vulnerability that enables authenticated attackers to maliciously crash the web application on the client-side.

Affected Systems and Versions

The vulnerability affects Mattermost versions 6.0 and earlier, with custom installations falling under the affected category due to the absence of sufficient parameter validation during post creation.

Exploitation Mechanism

Authenticated attackers can exploit the vulnerability by crafting posts with malicious parameters, triggering a client-side crash in the web application.

Mitigation and Prevention

This section provides insights into mitigating the CVE-2021-37863 vulnerability.

Immediate Steps to Take

It is recommended to update Mattermost to versions beyond 6.0, where the parameter validation issue has been addressed, thus preventing attackers from causing a client-side crash.

Long-Term Security Practices

Implementing a robust input validation mechanism and staying vigilant against potential security threats can enhance the overall security posture and prevent similar vulnerabilities in the future.

Patching and Updates

Regularly applying security patches and updates from Mattermost can help in addressing known vulnerabilities, including CVE-2021-37863, thereby ensuring a secure environment.