CVE-2004-0091: Jelsoft vBulletin

Medium severity, CVSS 4.3. EPSS: 1.2% chance of exploitation in the next 30 days.

NOTE: this issue has been disputed by the vendor. Cross-site scripting (XSS) vulnerability in register.php for unknown versions of vBulletin allows remote attackers to inject arbitrary HTML or web script via the reg_site (or possibly regsite) parameter. NOTE: the vendor has disputed this issue, saying "There is no hidden field called 'reg_site', nor any $reg_site variable anywhere in the vBulletin 2 or vBulletin 3 source code or templates, nor has it ever existed. We can only assume that this vulnerability was found in a site running code modified from that supplied by Jelsoft.

Affected products

• Jelsoft vBulletin: version 3.0_beta_2 only

Published 2004-02-17. Last modified 2026-06-16.