CVE-2009-2914 in Community Classifieds
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in index.php in XZero Community Classifieds 4.97.8 and earlier allows remote attackers to inject arbitrary web script or HTML via the name of an uploaded file. NOTE: the provenance of this information is unknown; the details are obtained solely from third party information.
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Analysis
by VulDB Data Team • 12/18/2017
The vulnerability described in CVE-2009-2914 represents a critical cross-site scripting flaw within the XZero Community Classifieds 4.97.8 software suite, specifically affecting the index.php component. This security weakness enables remote attackers to execute malicious web scripts or HTML code through manipulated file names uploaded to the system, creating a significant vector for unauthorized code execution and data manipulation. The vulnerability stems from insufficient input validation and sanitization mechanisms that fail to properly filter or escape user-supplied data before it is processed and displayed within the web application's interface.
The technical implementation of this flaw occurs when the application accepts file uploads without adequate validation of the filename parameter. When users upload files with maliciously crafted names containing script tags or other HTML content, the system fails to sanitize these inputs appropriately. This processing failure allows the malicious code to be stored within the application's database or file system and subsequently executed when the filename is rendered in web pages or displayed to other users. The vulnerability specifically targets the index.php script which likely handles the display or processing of uploaded file information, creating a direct pathway for attackers to inject persistent or reflected XSS payloads.
The operational impact of this vulnerability extends beyond simple script injection, as it can enable attackers to perform a wide range of malicious activities including session hijacking, credential theft, defacement of the classifieds platform, and potential escalation to more severe attacks. Attackers can craft file names containing JavaScript code that executes in the context of other users' browsers, potentially stealing cookies, session tokens, or personal information. The persistence of this vulnerability means that once exploited, malicious payloads can affect multiple users over time until the vulnerability is patched or the malicious files are removed from the system. This makes the vulnerability particularly dangerous for community-based platforms where user-generated content is prevalent and trusted.
Security mitigations for this vulnerability should focus on implementing comprehensive input validation and output encoding mechanisms throughout the application's data flow. The most effective approach involves sanitizing all user-supplied data, particularly filenames, by removing or encoding potentially dangerous characters such as angle brackets, script tags, and other HTML elements. Organizations should implement proper parameter validation that enforces strict naming conventions for uploaded files and employs HTML escaping when displaying user-generated content. Additionally, the application should implement Content Security Policy headers to prevent unauthorized script execution, and regular security audits should be conducted to identify similar vulnerabilities in other components of the classifieds platform. This vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws, and represents a classic example of how insufficient input validation creates persistent security risks in web applications. The ATT&CK framework categorizes this as a code injection technique under the broader category of web application attacks, highlighting the importance of proper data sanitization and validation in preventing such exploitation vectors.