CVE-2009-0312 in MoinMoin
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in the antispam feature (security/antispam.py) in MoinMoin 1.7 and 1.8.1 allows remote attackers to inject arbitrary web script or HTML via crafted, disallowed content.
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Analysis
by VulDB Data Team • 05/16/2025
The vulnerability identified as CVE-2009-0312 represents a critical cross-site scripting flaw within the MoinMoin wiki software version 1.7 and 1.8.1, specifically affecting the antispam security module located at security/antispam.py. This issue arises from inadequate input validation and sanitization mechanisms that fail to properly handle malicious content submitted through the antispam filtering system. The vulnerability stems from the software's inability to effectively sanitize user input before processing it through the antispam feature, creating a pathway for remote attackers to inject arbitrary web scripts or HTML code into the system.
The technical implementation of this vulnerability occurs when the antispam.py module processes content that contains malicious scripts or HTML tags without proper sanitization. Attackers can craft specific input sequences that bypass the antispam filtering mechanisms, allowing their malicious code to be executed within the context of other users' browsers. This occurs because the security module fails to properly escape or filter special characters and script tags that could be used to execute client-side code. The flaw essentially creates a trust boundary violation where user-supplied content that should be treated as untrusted is not properly sanitized before being processed or displayed.
The operational impact of this vulnerability is severe as it enables attackers to perform session hijacking, deface web pages, steal user credentials, or redirect users to malicious sites. When exploited, the XSS vulnerability allows attackers to execute arbitrary JavaScript code in the victim's browser, potentially leading to complete compromise of user sessions. The attack vector is particularly concerning because it leverages the legitimate antispam functionality of the system, making it more difficult for administrators to detect malicious activity. This vulnerability affects all users who interact with the wiki system and can be exploited through various means including wiki page edits, comments, or any content submission that passes through the vulnerable antispam module.
The vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws in web applications, and maps to several ATT&CK techniques including T1566 for social engineering and T1059 for command and scripting interpreter. Organizations using affected MoinMoin versions face significant risk of data breaches and system compromise, particularly in environments where wiki systems serve as collaboration platforms with sensitive information. The security implications extend beyond simple content manipulation to potential privilege escalation and persistent threats within the wiki environment. Mitigation strategies include immediate patching of the affected software versions, implementing comprehensive input validation and output encoding mechanisms, and deploying web application firewalls to detect and block suspicious script injection attempts.
This vulnerability demonstrates the critical importance of proper input sanitization in security modules, as the antispam feature itself is designed to protect against malicious content but inadvertently becomes a vector for exploitation. The flaw highlights the need for comprehensive security testing of all application components, particularly those handling user input, and underscores the principle that security controls should not create new attack surfaces. Organizations should implement regular security assessments and maintain updated threat intelligence to identify similar vulnerabilities in their web applications and wiki systems.