CVE-2026-35490CWE-863

changedetection.io has an Authentication Bypass via Decorator Ordering

Critical · published April 7, 2026

CVSS v3.1
9.8
EPSS
1%
Percentile
50.2
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00644 · 50.2th percentile
Weakness
CWE-863 · Incorrect Authorization
Published
2026-04-07T14:55Z
EPSS history
Timeline
  • 07 APR 14:55Z
    changedetection.io has an Authentication Bypass via Decorator Ordering
    cvelistv5