Exposure of Sensitive Information to an Unauthorized Actor
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.
CWE-200 - Information Exposure
An information exposure vulnerability is categorized as an information flow (IF) weakness, which can potentially allow unauthorized access to otherwise classified information in the application, such as confidential personal information (demographics, financials, health records, etc.), business secrets, and the application's internal environment.