CVE-2004-1823 in vBulletin
Summary
by MITRE
Multiple cross-site scripting (XSS) vulnerabilities in Jelsoft vBulletin 2.0 beta 3 through 3.0 can4 allows remote attackers to inject arbitrary web script or HTML via the (1) page parameter to showthread.php or (2) order parameter to forumdisplay.php.
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Analysis
by VulDB Data Team • 06/16/2025
The vulnerability described in CVE-2004-1823 represents a critical cross-site scripting flaw affecting Jelsoft vBulletin versions 2.0 beta 3 through 3.0. This vulnerability falls under the CWE-79 weakness category, which specifically addresses cross-site scripting vulnerabilities where untrusted data is improperly incorporated into web pages without proper sanitization or encoding. The flaw exists in the forum software's handling of user-supplied input parameters, creating a pathway for malicious actors to inject arbitrary web scripts or HTML code into web pages viewed by other users.
The technical implementation of this vulnerability occurs through two distinct attack vectors within the vBulletin platform. The first vector involves the page parameter in the showthread.php script, while the second vector targets the order parameter in forumdisplay.php. Both parameters fail to properly validate or sanitize incoming data before incorporating it into the dynamic web content generation process. This lack of input validation allows attackers to craft malicious payloads that get executed in the context of other users' browsers when they view affected pages.
The operational impact of this vulnerability is significant and far-reaching within the context of online forums and community platforms. Attackers can leverage these XSS flaws to execute malicious scripts in the browsers of unsuspecting forum users, potentially leading to session hijacking, credential theft, or the redirection of users to malicious websites. The vulnerability affects the core functionality of the forum software, as it undermines the trust and security assumptions users have when interacting with the platform. Users may unknowingly execute malicious code that could steal their session cookies, redirect them to phishing sites, or perform unauthorized actions on their behalf.
From a threat modeling perspective, this vulnerability aligns with ATT&CK technique T1531 for "Account Access Removal" and T1071.001 for "Application Layer Protocol: Web Protocols" as it exploits the web application layer to compromise user sessions and manipulate web traffic. The attack surface is particularly concerning for community platforms where user-generated content is prevalent, as the vulnerability can be exploited by any registered user or even unauthenticated attackers depending on the specific implementation details. Organizations relying on vulnerable vBulletin installations face potential data breaches, reputational damage, and compliance violations due to the exposure of user session information and potential unauthorized access to forum resources.
The recommended mitigation strategies include immediate patching of the vBulletin software to the latest available versions that address these XSS vulnerabilities. Additionally, implementing proper input validation and output encoding mechanisms at the application level can prevent similar issues from occurring in the future. Web application firewalls should be configured to detect and block suspicious script injection attempts, while security headers such as Content Security Policy should be implemented to provide additional protection against XSS attacks. Regular security audits and penetration testing of web applications are essential to identify and remediate similar vulnerabilities before they can be exploited by malicious actors in the wild.