1. Introduction
The XOOPS viewtopic.php Multiple Parameter XSS vulnerability allows attackers to inject malicious code into web pages viewed by other users. This is a cross-site scripting (XSS) flaw within the weblinks module of the XOOPS content management system. Successful exploitation can lead to account takeover, data theft, or website defacement. Systems running vulnerable versions of XOOPS are at risk. Likely impact is high on confidentiality and integrity, with moderate potential for availability disruption.
2. Technical Explanation
The vulnerability exists because the ‘viewtopic.php’ file in the ‘/modules/newbb’ directory does not properly filter user-supplied data within URL parameters. This allows an attacker to inject arbitrary HTML and JavaScript code into a web page displayed to other users. The CVE identifier for this issue is CVE-2004-2756.
- Root cause: Insufficient input validation on URL parameters processed by ‘viewtopic.php’.
- Exploit mechanism: An attacker crafts a malicious URL containing JavaScript code within a vulnerable parameter, such as the ‘topic_id’ or ‘mode’ parameter. When another user clicks this link, the injected script executes in their browser. For example, an attacker could create a URL like
http://example.com/modules/newbb/viewtopic.php?topic_id= - Scope: XOOPS installations using the weblinks module are affected. Specific versions were not provided in the source data, so all versions should be considered at risk until patched.
3. Detection and Assessment
Confirming vulnerability requires checking the version of XOOPS installed and testing for the presence of the flaw.
- Quick checks: Check the XOOPS version via the administration interface (usually found at
http://example.com/xoopsadmin). - Scanning: Nessus plugin ID 1008849 may detect this vulnerability, but results should be verified manually.
- Logs and evidence: Examine web server access logs for requests containing suspicious JavaScript code in the URL parameters of ‘viewtopic.php’. Look for patterns like `