CVE-2005-2539: Multiple cross-site scripting (XSS) vulnerabilities in FlatNuke 2.5.5 and possibly earlier versions allow r...

Security readout for executives and security teams

CVE-2005-2539 is an old cross-site scripting issue in FlatNuke 2.5.5 and possibly earlier. An attacker could make vulnerable pages run attacker-supplied script or HTML in a user’s browser. Business risk is mainly account abuse, content manipulation, or session theft on exposed legacy sites. Exposure is most likely limited to internet-facing or intranet FlatNuke deployments running version 2.5.5 or possibly earlier. Organizations with legacy PHP CMS assets, archived sites, or forgotten microsites should check specifically for FlatNuke rather than relying on product inventory names alone. Prioritize this if FlatNuke is still reachable from users or the internet. The vulnerability is old, but legacy CMS exposure can persist unnoticed. If no FlatNuke instances exist, no direct action is needed beyond documenting the inventory result. Mitigation focus: Inventory public and internal sites for FlatNuke 2.5.5 or earlier.; Check FlatNuke vendor or archival guidance for fixed versions or migration advice.; Retire or isolate unsupported FlatNuke deployments where practical..

Prepared

Jun 29, 2026, 18:40 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.