CVE-2015-2940 in MediaWiki
Summary
by MITRE
Cross-site request forgery (CSRF) vulnerability in the CheckUser extension for MediaWiki allows remote attackers to hijack the authentication of certain users for requests that retrieve sensitive user information via unspecified vectors.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 05/03/2022
The CVE-2015-2940 vulnerability represents a critical cross-site request forgery flaw within the CheckUser extension for MediaWiki platforms, a widely deployed wiki software solution used by organizations ranging from small communities to large enterprises. This vulnerability specifically targets the authentication mechanisms of MediaWiki systems, creating a pathway for remote attackers to exploit user sessions and gain unauthorized access to sensitive user data. The CheckUser extension, designed to allow administrators to view user information including IP addresses and edit history, becomes a vector for malicious exploitation when proper CSRF protection mechanisms are absent or flawed. The vulnerability's impact extends beyond simple information disclosure, as it enables attackers to manipulate user sessions and potentially escalate privileges within the MediaWiki environment. The unspecified vectors mentioned in the description suggest that the attack could occur through various delivery mechanisms including malicious web pages, email attachments, or compromised third-party websites that leverage the victim's authenticated session with the MediaWiki instance.
The technical implementation of this CSRF vulnerability stems from the absence of proper anti-CSRF token validation within the CheckUser extension's request handling process. When users navigate to pages that interact with the CheckUser functionality, the system should verify that requests originate from legitimate sources and not from malicious third-party domains. However, the flaw allows attackers to craft specially crafted requests that, when executed by an authenticated user, can retrieve sensitive information without the user's knowledge or consent. This type of vulnerability aligns with CWE-352, which specifically addresses Cross-Site Request Forgery weaknesses in software applications. The flaw operates by exploiting the trust relationship between the web application and the user's browser, where the browser automatically includes authentication cookies with requests to the target domain, enabling attackers to perform actions on behalf of authenticated users. The vulnerability's exploitation requires minimal user interaction, often limited to visiting a malicious website while maintaining an active session with the vulnerable MediaWiki instance, making it particularly dangerous in environments where users frequently access multiple websites.
The operational impact of CVE-2015-2940 extends significantly beyond immediate data theft, as it can lead to comprehensive session hijacking and privilege escalation within MediaWiki environments. Attackers can potentially access detailed user information including IP addresses, edit histories, and other sensitive metadata that could be used for social engineering attacks or further targeting of specific users. In enterprise or institutional environments where MediaWiki is used for internal documentation, collaboration, or knowledge management, this vulnerability could expose confidential information about user activities, system access patterns, and organizational data structures. The attack vector's remote nature means that exploitation can occur from anywhere in the world without requiring physical access to the target network or system. Organizations using MediaWiki for sensitive operations such as healthcare records, financial data management, or government information systems face particularly severe risks from this vulnerability. The potential for automated exploitation through web-based attack frameworks makes this vulnerability especially dangerous, as attackers can scale their efforts across multiple targets simultaneously.
Mitigation strategies for CVE-2015-2940 should prioritize immediate patching of the CheckUser extension to implement proper CSRF token validation mechanisms. Organizations should ensure that all MediaWiki installations receive the latest security updates from the official MediaWiki project, as the vulnerability was addressed through the implementation of anti-CSRF tokens that validate request authenticity. Network administrators should implement additional security controls including proper session management, authentication token rotation, and monitoring for unusual access patterns that might indicate exploitation attempts. The implementation of Content Security Policy headers and strict SameSite cookie attributes can provide additional layers of protection against CSRF attacks, aligning with recommended practices from the OWASP Foundation and NIST guidelines. Security teams should conduct comprehensive vulnerability assessments of their MediaWiki installations to identify any other extensions or components that might be vulnerable to similar CSRF flaws, as the presence of one vulnerability often indicates potential issues with the overall security architecture. Regular security audits and penetration testing should be conducted to ensure that CSRF protections remain effective against evolving attack techniques, with particular attention to ensuring that all user-facing web forms and API endpoints properly validate request sources and authentication tokens. The vulnerability's classification under ATT&CK technique T1566.001 highlights the importance of defending against credential harvesting and session hijacking attacks that leverage web application weaknesses to gain unauthorized access to user accounts and sensitive information.