CVE-2017-18920 : What You Need to Know

A problem was found in Mattermost Server prior to version 3.6.2 where the WebSocket functionality does not adhere to the Same Origin Policy.

Understanding CVE-2017-18920

An issue was discovered in Mattermost Server before version 3.6.2, where the WebSocket feature does not follow the Same Origin Policy.

What is CVE-2017-18920?

CVE-2017-18920 is a vulnerability in Mattermost Server that allows WebSocket functionality to bypass the Same Origin Policy, potentially leading to security risks.

The Impact of CVE-2017-18920

This vulnerability could be exploited by malicious actors to perform cross-site scripting attacks, potentially compromising the confidentiality and integrity of data transmitted via WebSocket connections.

Technical Details of CVE-2017-18920

This section provides more technical insights into the vulnerability.

Vulnerability Description

The WebSocket functionality in Mattermost Server prior to version 3.6.2 does not adhere to the Same Origin Policy, allowing for potential security breaches.

Affected Systems and Versions

Affected Version: Mattermost Server before 3.6.2

Exploitation Mechanism

Attackers can exploit this vulnerability to launch cross-site scripting attacks by bypassing the Same Origin Policy, potentially gaining unauthorized access to sensitive data.

Mitigation and Prevention

Protecting systems from CVE-2017-18920 requires immediate actions and long-term security practices.

Immediate Steps to Take

Upgrade Mattermost Server to version 3.6.2 or later to mitigate the vulnerability.
Monitor WebSocket connections for any suspicious activity.

Long-Term Security Practices

Implement strict Same Origin Policy enforcement for WebSocket functionality.
Regularly update and patch software to address security vulnerabilities.
Conduct security assessments and penetration testing to identify and remediate potential weaknesses.
Educate users and administrators on secure WebSocket usage.

Patching and Updates

Ensure that all software components, including Mattermost Server, are regularly updated with the latest security patches to prevent exploitation of known vulnerabilities.