CVE-2026-40295
Analyzed Analyzed - Analysis Complete
BaseFortify

Publication date: 2026-05-22

Last updated on: 2026-05-29

Assigner: GitHub, Inc.

Description
Devise is an authentication solution for Rails based on Warden. In versions 5.0.3 and below, when the Timeoutable module is enabled in Devise, the FailureApp#redirect_url method returns request.referrer β€” the HTTP Referer header, which is attacker-controllable β€” without validation for any non-GET request that results in a session timeout. An attacker who hosts a page with an auto-submitting cross-origin form can cause a victim with an expired Devise session to be redirected to an arbitrary external URL. This contrasts with the GET timeout path (which uses server-side attempted_path) and Devise's own store_location_for mechanism (which strips external hosts via extract_path_from_location), both of which are protected; only the non-GET timeout redirect path is unprotected. Expired-session users can be silently redirected from the trusted app domain to attacker-controlled URLs, enabling phishing and malware delivery while bypassing browser warnings. Note: Rails' built-in open-redirect protection does not mitigate this issue. Devise::FailureApp is an ActionController::Metal app with its own isolated copy of the relevant redirect configuration, so config.action_controller.action_on_open_redirect = :raise (and the older raise_on_open_redirects setting) do not reach it. This issue has been fixed in version 5.0.4.
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Meta Information
Published
2026-05-22
Last Modified
2026-05-29
Generated
2026-06-15
EPSS Evaluated
2026-06-14
NVD
EUVD
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
heartcombo devise to 5.0.4 (exc)
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Exploitability
CWE
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KEV
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CWE ID Description
CWE-601 The web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a redirect.
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