CVE-2004-2242 in Phorum
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in search.php in Phorum, possibly 5.0.7 beta and earlier, allows remote attackers to inject arbitrary HTML or web script via the subject parameter.
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Analysis
by VulDB Data Team • 04/27/2025
The vulnerability identified as CVE-2004-2242 represents a classic cross-site scripting flaw within the Phorum web forum software, specifically affecting versions 5.0.7 beta and earlier. This security weakness resides in the search.php script where user input is not properly sanitized before being rendered back to web browsers. The vulnerability manifests when attackers exploit the subject parameter, which serves as an entry point for injecting malicious HTML or JavaScript code directly into the application's response. Such an attack vector enables adversaries to execute arbitrary scripts within the context of other users' browsers, potentially compromising their sessions and accessing sensitive information.
The technical implementation of this vulnerability aligns with CWE-79, which categorizes cross-site scripting as a code injection flaw where untrusted data is incorporated into web pages without proper validation or encoding. The flaw occurs because the Phorum application fails to implement adequate input sanitization measures when processing the subject parameter in the search functionality. This oversight creates a persistent security gap where malicious actors can craft specially formatted subject strings containing HTML tags or JavaScript code that gets executed when other users view the search results. The vulnerability is particularly concerning because it operates at the user interface level, making it accessible to attackers without requiring elevated privileges or complex exploitation techniques.
The operational impact of CVE-2004-2242 extends beyond simple data theft, as it can facilitate session hijacking, credential theft, and the redirection of users to malicious websites. When exploited, this vulnerability allows attackers to inject scripts that can steal cookies, modify page content, or perform actions on behalf of authenticated users. The attack surface is particularly broad since search functionality is a core feature of any forum system, making it highly likely that users will interact with the vulnerable code path. From an attacker's perspective, this vulnerability maps to the attack technique described in the MITRE ATT&CK framework under T1059.007 for scripting languages and T1531 for credential access, as it enables the execution of malicious code within legitimate user sessions.
Mitigation strategies for this vulnerability should prioritize immediate input validation and output encoding within the Phorum application. The recommended approach involves implementing strict sanitization of all user-provided input, particularly the subject parameter in search.php, through the use of HTML entity encoding before rendering content to browsers. System administrators should upgrade to patched versions of Phorum where the vulnerability has been addressed through proper input validation mechanisms. Additionally, implementing Content Security Policy headers can provide an additional layer of protection by restricting the sources from which scripts can be loaded and executed. The vulnerability also underscores the importance of regular security assessments and input validation testing, particularly for web applications handling user-generated content, as outlined in OWASP Top Ten security guidelines for preventing cross-site scripting attacks. Organizations should also consider implementing web application firewalls and monitoring for suspicious input patterns to detect potential exploitation attempts.