CVE-2026-73319: Xenforo

Medium severity, CVSS 6.1. EPSS: 0.4% chance of exploitation in the next 30 days.

XenForo before 2.3.13 contains a cross-site scripting vulnerability in the dynamic redirect handler that allows unauthenticated attackers to execute arbitrary JavaScript in the board origin by crafting a malicious javascript: URI that bypasses host validation. Attackers can embed the board hostname in the URI authority component and use percent-encoded newlines to evade server-side filters, causing authenticated users who perform a Follow action to execute attacker-supplied JavaScript in their browser.

Affected products

• Xenforo Xenforo: before 2.3.13 (fixed in 2.3.13)

Published 2026-09-08. Last modified 2026-09-11.