Description
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
References2
- github.com/dgtlmoon/changedetection.io/security/advisories/GHSA… ExploitMitigationVendor Advisory
- github.com/dgtlmoon/changedetection.io/security/advisories/GHSA… ExploitMitigationVendor Advisory
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 46 · as of 12 November 2026
- CWE
- CWE-863
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