CVE-2026-27508: Smoothwall Express

Medium severity, CVSS 6.1. EPSS: 0.3% chance of exploitation in the next 30 days.

Smoothwall Express versions prior to 3.1 Update 13 contain a reflected cross-site scripting vulnerability in the /redirect.cgi endpoint due to improper sanitation of the url parameter. Attackers can craft malicious URLs with javascript: schemes that execute arbitrary JavaScript in victims' browsers when clicked through the unsanitized link.

Affected products

• Smoothwall Smoothwall Express: up to and including 3.0; version 3.1 only

Published 2026-03-30. Last modified 2026-06-17.