CVE-2020-15164 : Exploit Details and Defense Strategies

In Scratch Login (MediaWiki extension) before version 1.1, an authentication bypass vulnerability allows any account to be logged into using the same username with specific characters. This issue affects all users on any wiki utilizing this extension.

Understanding CVE-2020-15164

This CVE describes an authentication bypass vulnerability in the mediawiki-scratch-login extension.

What is CVE-2020-15164?

The vulnerability in the Scratch Login extension allows accounts to be accessed by using usernames with certain characters that are treated as whitespace and trimmed by MediaWiki.

The Impact of CVE-2020-15164

The vulnerability poses a critical risk with a CVSS base score of 10, high confidentiality and integrity impacts, affecting all users of the extension.

Technical Details of CVE-2020-15164

This section provides more technical insights into the CVE.

Vulnerability Description

The issue arises from the mishandling of usernames with specific characters, allowing unauthorized access to accounts.

Affected Systems and Versions

Product: mediawiki-scratch-login
Vendor: InternationalScratchWiki
Versions affected: < 1.1

Exploitation Mechanism

Attackers can exploit this vulnerability by using usernames with leading, trailing, or repeated underscore(s) as whitespace.

Mitigation and Prevention

Protecting systems from this vulnerability is crucial.

Immediate Steps to Take

Upgrade to version 1.1 or newer of the mediawiki-scratch-login extension.
Avoid using usernames with characters that can be treated as whitespace.

Long-Term Security Practices

Regularly monitor and audit user authentication processes.
Educate users on secure username practices to prevent similar issues.

Patching and Updates

Apply patches and updates provided by the extension vendor to address this vulnerability.