CVE-2008-6437 in PHPFreeForum
Summary
by MITRE
Multiple cross-site scripting (XSS) vulnerabilities in PHPFreeForum 1.0 RC2 and earlier allow remote attackers to inject arbitrary web script or HTML via the (1) message parameter to error.php, and the (2) nickname and (3) randomid parameters to part/menu.php.
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Analysis
by VulDB Data Team • 09/15/2025
The vulnerability identified as CVE-2008-6437 represents a critical security flaw in PHPFreeForum version 1.0 RC2 and earlier installations, exposing the application to multiple cross-site scripting attack vectors that could enable malicious actors to execute arbitrary code within the context of user browsers. This vulnerability falls under the Common Weakness Enumeration category CWE-79, which specifically addresses cross-site scripting flaws that occur when untrusted data is improperly incorporated into web pages without proper validation or sanitization. The flaw manifests in three distinct attack vectors within the forum's core functionality, making it particularly dangerous as it provides multiple pathways for exploitation.
The technical implementation of this vulnerability stems from inadequate input validation mechanisms within the PHPFreeForum application's error handling and user interface components. Attackers can exploit the vulnerability by manipulating three separate parameters in different script files. The first vector involves the message parameter in error.php, where user-provided input flows directly into the web page output without proper HTML encoding or sanitization. The second and third vectors target the nickname and randomid parameters in part/menu.php, where similar input processing errors allow malicious payloads to be injected into the application's response. These parameters are typically used for user identification and session management within the forum environment, making them prime targets for exploitation.
The operational impact of this vulnerability extends beyond simple script injection, as it can enable attackers to perform various malicious activities within the compromised environment. An attacker could craft specially formatted requests that, when processed by the vulnerable application, would execute JavaScript code in the victim's browser, potentially leading to session hijacking, credential theft, or redirection to malicious sites. The vulnerability's persistence across multiple components of the application architecture means that even if one attack vector is patched, others remain exploitable, creating a broader attack surface that could compromise user data and application integrity. Additionally, the vulnerability could be leveraged to deface the forum, inject malicious advertisements, or establish persistent backdoors within the user base.
Mitigation strategies for CVE-2008-6437 should prioritize immediate patching of the affected PHPFreeForum versions, with comprehensive input validation and output encoding implemented across all user-controllable parameters. Organizations should implement proper HTML escaping mechanisms for all dynamic content, particularly in error handling and user interface components. The solution approach aligns with the ATT&CK framework's mitigation strategies for web application attacks, specifically targeting the execution and persistence phases of the attack lifecycle. Regular security auditing of web applications should include thorough examination of input validation mechanisms, and developers should adopt secure coding practices that prevent user input from being directly incorporated into web page output without proper sanitization. The vulnerability also underscores the importance of keeping web applications updated with the latest security patches and implementing comprehensive security monitoring to detect and respond to exploitation attempts.