CVE-2013-4569 in MediaWiki
Summary
by MITRE
The CleanChanges extension for MediaWiki before 1.19.9, 1.20.x before 1.20.8, and 1.21.x before 1.21.3, when "Group changes by page in recent changes and watchlist" is enabled, allows remote attackers to obtain sensitive information (revision-deleted IPs) via the Recent Changes page.
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Analysis
by VulDB Data Team • 01/11/2022
The vulnerability identified as CVE-2013-4569 affects the CleanChanges extension for MediaWiki, a widely used wiki software platform that powers numerous websites including Wikipedia. This security flaw exists in versions prior to 1.19.9, 1.20.8, and 1.21.3, representing a critical information disclosure issue that undermines the platform's access controls and data protection mechanisms. The vulnerability specifically manifests when the "Group changes by page in recent changes and watchlist" feature is enabled, which is a common configuration for many MediaWiki installations seeking to organize user activity more effectively.
The technical implementation of this vulnerability stems from insufficient access control validation within the CleanChanges extension's handling of revision-deleted IP addresses. When users with appropriate privileges attempt to view recent changes, the extension fails to properly verify whether the requesting user has authorization to access the specific revision data being displayed. This flaw allows remote attackers to bypass normal access restrictions that should prevent viewing of deleted IP addresses, which are typically protected under revision deletion policies to maintain user privacy and security. The vulnerability operates through the Recent Changes page interface, which serves as a public-facing activity feed that aggregates user modifications across the wiki platform.
The operational impact of this vulnerability extends beyond simple information disclosure, as it represents a significant breach in the trust model of MediaWiki installations. Attackers can exploit this weakness to obtain sensitive IP address information that should remain hidden from unauthorized users, potentially enabling them to track user activities, identify contributors, or conduct targeted attacks against specific individuals. This information leakage poses particular risks for wikis that host sensitive content or operate in environments where user privacy is paramount. The vulnerability affects not only individual user privacy but also the overall security posture of organizations relying on MediaWiki for collaborative platforms, document management, or knowledge sharing systems.
Organizations affected by this vulnerability should immediately upgrade to the patched versions of MediaWiki that address the access control flaw in the CleanChanges extension. The mitigation strategy involves implementing the official security patches released by the MediaWiki development team, which correct the insufficient validation of user permissions when accessing revision data. Additionally, administrators should review their current extension configurations and disable the problematic "Group changes by page" feature if immediate patching is not feasible. This vulnerability aligns with CWE-284, which addresses improper access control, and represents a specific implementation weakness in the authorization mechanisms of the MediaWiki platform. From an ATT&CK framework perspective, this vulnerability maps to techniques involving privilege escalation and information gathering, as it allows attackers to access data that should be restricted to authorized personnel only. The remediation process should include comprehensive testing of the patched environment to ensure that legitimate user access continues to function properly while the security vulnerability is effectively closed.