CVE-2021-37864 : Exploit Details and Defense Strategies

Users can view the contents of an archived channel when access is explicitly denied by the system admin

Understanding CVE-2021-37864

This CVE involves Mattermost 6.1 and earlier versions failing to validate permissions properly, allowing authenticated users to access archived channel contents against system administrator restrictions.

What is CVE-2021-37864?

The vulnerability in Mattermost allows authenticated users to view the contents of archived channels, even when access to this content is denied by system administrators. This unauthorized access occurs through direct API interaction.

The Impact of CVE-2021-37864

With a CVSS base score of 2.6 (Low severity), this vulnerability could lead to unauthorized exposure of sensitive information in archived channels to authenticated users. It poses a threat to data confidentiality.

Technical Details of CVE-2021-37864

This section will delve into the vulnerability description, affected systems and versions, as well as the exploitation mechanism.

Vulnerability Description

The issue originates from Mattermost 6.1 and earlier versions inadequately checking permissions, granting authenticated users access to view contents of archived channels that should be restricted.

Affected Systems and Versions

Mattermost versions prior to 6.2 are impacted by this vulnerability, allowing unauthorized access to archived channel contents.

Exploitation Mechanism

Authenticated users can exploit this vulnerability by directly accessing Mattermost APIs to view the contents of archived channels, bypassing administrator restrictions.

Mitigation and Prevention

Learn about the immediate steps to take as well as long-term security practices and the importance of patching and updates.

Immediate Steps to Take

System administrators should restrict access to sensitive information and consider upgrading to patched versions.

Long-Term Security Practices

Employ robust access control mechanisms and regularly monitor and audit user activities to prevent unauthorized access.

Patching and Updates

Ensure the timely installation of security patches provided by Mattermost to address this vulnerability.