CVE-2013-7444 in MediaWiki
Summary
by MITRE
The Special:Contributions page in MediaWiki before 1.22.0 allows remote attackers to determine if an IP is autoblocked via the "Change block" text.
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Analysis
by VulDB Data Team • 06/14/2022
The vulnerability described in CVE-2013-7444 affects MediaWiki versions prior to 1.22.0 and specifically targets the Special:Contributions page functionality. This issue represents a security disclosure flaw that enables remote attackers to perform information gathering attacks by exploiting the response behavior of the web application. The vulnerability manifests when users access the Special:Contributions page with an IP address that has been autoblocked, allowing attackers to infer the autoblock status through the presence or absence of specific text elements in the page response. This type of information disclosure vulnerability falls under the category of indirect information leakage, where the application's behavior reveals sensitive status information that should remain confidential.
The technical implementation of this vulnerability stems from the way MediaWiki handles user account and IP address blocking states within its contribution tracking interface. When an IP address is autoblocked due to violations of the wiki's policies, the system should not reveal this autoblock status through the Special:Contributions page interface. However, the flawed implementation causes the page to display different text elements or response patterns depending on whether the IP is autoblocked or not. This differential response behavior creates a side-channel attack vector that allows remote adversaries to determine autoblock status without requiring authentication or privileged access. The vulnerability specifically relates to the application's handling of user input validation and response generation, where the system's reaction to different IP states inadvertently exposes administrative information.
The operational impact of this vulnerability extends beyond simple information disclosure, as it provides attackers with valuable intelligence for planning more sophisticated attacks. By determining which IP addresses are autoblocked, adversaries can identify potentially compromised accounts or targets that have violated wiki policies, which could be leveraged for targeted attacks or to avoid detection by avoiding known autoblocked IP ranges. This information leakage could enable attackers to conduct more effective social engineering campaigns, identify high-value targets for further reconnaissance, or develop strategies to circumvent access controls by understanding the blocking patterns of the wiki system. The vulnerability essentially undermines the security model of the MediaWiki platform by exposing administrative state information that should remain private and protected.
Security mitigations for this vulnerability require immediate patching of MediaWiki installations to version 1.22.0 or later, where the issue has been resolved through proper input handling and response normalization. Organizations should implement comprehensive testing procedures to ensure that all user interface elements respond consistently regardless of user or IP blocking status. The fix typically involves modifying the Special:Contributions page to standardize its response behavior, ensuring that autoblock information is not exposed through text content or response patterns. Additionally, system administrators should conduct regular security audits of their MediaWiki installations, verify proper access controls, and implement monitoring for unusual access patterns that might indicate exploitation attempts. This vulnerability aligns with CWE-200, which covers information exposure, and could potentially be leveraged as part of broader attack strategies that follow the ATT&CK framework's reconnaissance phase, specifically targeting information gathering techniques that exploit application behavior patterns.