CVE-2026-35490: Webtechnologies Changedetection

Critical severity, CVSS 9.8. EPSS: 0.6% chance of exploitation in the next 30 days.

changedetection.io is a free open source web page change detection tool. Prior to 0.54.8, the @login_optionally_required decorator is placed before (outer to) @blueprint.route() instead of after it. In Flask, @route() must be the outermost decorator because it registers the function it receives. When the order is reversed, @route() registers the original undecorated function, and the auth wrapper is never in the call chain. This silently disables authentication on these routes. This vulnerability is fixed in 0.54.8.

Affected products

• Webtechnologies Changedetection: before 0.54.8 (fixed in 0.54.8)

Published 2026-04-07. Last modified 2026-06-17.