CVE-2014-2243 in MediaWiki
Summary
by MITRE
includes/User.php in MediaWiki before 1.19.12, 1.20.x and 1.21.x before 1.21.6, and 1.22.x before 1.22.3 terminates validation of a user token upon encountering the first incorrect character, which makes it easier for remote attackers to obtain access via a brute-force attack that relies on timing differences in responses to incorrect token guesses.
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Analysis
by VulDB Data Team • 04/12/2025
The vulnerability identified as CVE-2014-2243 affects MediaWiki versions prior to specific patch releases, creating a significant security weakness in the user authentication token validation process. This flaw resides within the includes/User.php file and represents a timing side-channel attack vector that undermines the integrity of the authentication system. The vulnerability manifests when the system processes user tokens and terminates validation immediately upon encountering the first incorrect character rather than performing a complete validation check. This behavior creates measurable timing differences between successful and failed token attempts, which malicious actors can exploit through carefully crafted brute-force attacks.
The technical implementation of this vulnerability stems from improper error handling during token validation procedures. When MediaWiki validates user tokens, it should execute a constant-time comparison to prevent timing-based attacks that could reveal information about the correct token. However, the flawed implementation stops processing at the first mismatched character, creating observable time differences in response times. Attackers can measure these timing variations to infer the correct token characters incrementally, significantly reducing the complexity of brute-force attacks against user sessions and authentication mechanisms. This issue directly relates to CWE-204, which addresses information exposure through timing differences, and represents a classic example of a timing attack vulnerability that compromises the security of authentication systems.
The operational impact of this vulnerability extends beyond simple session hijacking to encompass broader authentication system compromise. Remote attackers can leverage this timing discrepancy to systematically determine valid user tokens through automated brute-force mechanisms, potentially gaining unauthorized access to user accounts and system resources. The vulnerability affects multiple MediaWiki release branches, indicating a widespread exposure across various installations that rely on the platform for content management and user authentication. This creates substantial risk for organizations using MediaWiki for sensitive operations, as the timing-based attack vector allows for efficient credential guessing without triggering typical rate-limiting mechanisms that might otherwise prevent such attacks.
Security mitigations for CVE-2014-2243 require immediate patching of affected MediaWiki installations to the corrected versions that implement proper constant-time token validation. Organizations should also implement additional security controls including rate limiting, account lockout mechanisms, and monitoring for unusual authentication patterns that might indicate timing-based attacks. The fix addresses the underlying issue by ensuring that token validation processes complete regardless of character mismatches, thereby eliminating the timing side-channel that attackers exploit. From an operational perspective, system administrators should conduct comprehensive vulnerability assessments of their MediaWiki installations and verify that all affected versions have been properly updated to prevent exploitation. This vulnerability also highlights the importance of implementing proper cryptographic practices in authentication systems and aligns with ATT&CK technique T1212 which focuses on exploitation of information disclosure vulnerabilities through timing attacks. Organizations should consider implementing additional security monitoring to detect potential exploitation attempts and maintain awareness of similar timing-based vulnerabilities that might affect other authentication systems within their infrastructure.