CVE-2020-25828 : Security Advisory and Response

An issue was discovered in MediaWiki before 1.31.10 and 1.32.x through 1.34.x before 1.34.4. The non-jqueryMsg version of mw.message().parse() doesn't escape HTML, potentially exposing vulnerabilities.

Understanding CVE-2020-25828

This CVE identifies a security flaw in MediaWiki versions prior to 1.31.10 and 1.32.x through 1.34.4 that could lead to HTML injection attacks.

What is CVE-2020-25828?

The vulnerability arises from the lack of HTML escaping in the non-jqueryMsg version of mw.message().parse(), impacting both message contents and parameters based on user input.

The Impact of CVE-2020-25828

Allows malicious users to inject arbitrary HTML code into messages and parameters
Increases the risk of cross-site scripting (XSS) attacks

Technical Details of CVE-2020-25828

MediaWiki's mw.message().parse() function is susceptible to HTML injection due to inadequate HTML escaping.

Vulnerability Description

The vulnerability allows attackers to insert malicious HTML code into messages and parameters, potentially compromising the integrity of the system.

Affected Systems and Versions

MediaWiki versions before 1.31.10 and 1.32.x through 1.34.4

Exploitation Mechanism

Attackers can exploit this vulnerability by injecting crafted HTML code into messages or parameters, leading to XSS attacks.

Mitigation and Prevention

To address CVE-2020-25828, follow these mitigation strategies:

Immediate Steps to Take

Update MediaWiki to version 1.31.10 or 1.34.4 to patch the vulnerability
Implement input validation to sanitize user-generated content

Long-Term Security Practices

Regularly monitor and audit code for security vulnerabilities
Educate developers on secure coding practices to prevent similar issues

Patching and Updates

Apply security patches promptly to ensure protection against known vulnerabilities