CVE-2013-4303 in MediaWiki
Summary
by MITRE
includes/libs/IEUrlExtension.php in the MediaWiki API in MediaWiki 1.19.x before 1.19.8, 1.20.x before 1.20.7, and 1.21.x before 1.21.2 does not properly detect extensions when there are an even number of "." (period) characters in a string, which allows remote attackers to conduct cross-site scripting (XSS) attacks via the siprop parameter in a query action to wiki/api.php.
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Analysis
by VulDB Data Team • 12/25/2024
The vulnerability identified as CVE-2013-4303 represents a critical cross-site scripting flaw in the MediaWiki API component that affects multiple versions of the popular wiki platform. This security issue resides within the includes/libs/IEUrlExtension.php file and specifically targets the URL extension detection mechanism used by the MediaWiki API. The flaw manifests when processing strings containing an even number of period characters, creating a condition where the system fails to properly validate and sanitize input parameters before processing them as part of the API request flow.
The technical implementation of this vulnerability stems from improper string parsing logic within the MediaWiki API's URL extension handling functionality. When the system encounters a string with an even number of periods, the internal detection algorithm becomes confused about the proper extension boundaries, leading to a failure in the expected validation checks. This misinterpretation occurs during the processing of the siprop parameter in API queries sent to wiki/api.php, where the system should enforce strict input sanitization but instead allows malicious payloads to bypass security controls. The vulnerability operates at the application layer and can be exploited through carefully crafted API requests that manipulate the period character count in URL strings.
The operational impact of CVE-2013-4303 extends beyond simple XSS exploitation, as it enables attackers to inject malicious scripts into wiki pages that can persist and affect all users interacting with the compromised system. This vulnerability specifically targets the MediaWiki API's handling of the siprop parameter, which is commonly used for various site information requests, making it a high-value target for attackers seeking to compromise wiki environments. The flaw allows for persistent XSS attacks that can execute malicious JavaScript in the context of a victim's browser, potentially enabling session hijacking, data theft, or further exploitation of the wiki platform. This issue affects organizations relying on MediaWiki for collaborative content management, documentation, and knowledge sharing platforms, where unauthorized script execution could lead to complete system compromise.
Organizations affected by this vulnerability should implement immediate mitigations including applying the official patches released by the MediaWiki project for versions 1.19.8, 1.20.7, and 1.21.2, which address the flawed URL extension detection logic. Network administrators should also consider implementing web application firewalls to detect and block malicious API requests containing suspicious period patterns, while security teams should conduct comprehensive audits of all MediaWiki installations to ensure proper patch management. The vulnerability aligns with CWE-79, which describes cross-site scripting flaws in web applications, and can be mapped to ATT&CK technique T1213.002 for data from information repositories, as it enables unauthorized access to wiki content through script injection. Additionally, this issue demonstrates characteristics of T1059.007 for command and scripting interpreter, as the XSS payload can execute malicious commands within the browser context of authenticated users. System administrators should also consider implementing input validation controls that specifically target period character patterns and enforce proper URL sanitization before any API requests are processed, as the root cause lies in the insufficient validation of period-based string parsing logic.