CVE-2026-40295 (GCVE-0-2026-40295)
Vulnerability from cvelistv5 – Published: 2026-05-22 19:10 – Updated: 2026-05-26 13:10
VLAI
EPSS
VEX
Title
Devise: Open Redirect via Unvalidated `request.referrer` in Timeoutable Session Timeout Handler
Summary
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 — the HTTP Referer header, which is attacker-controllable — 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.
Severity
6.1 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-26 13:09 UTC
CWE
- CWE-601 - URL Redirection to Untrusted Site ('Open Redirect')
Assigner
GitHub_M
CNA
References
2 references
| URL | Tags |
|---|---|
| https://github.com/heartcombo/devise/security/adv… | x_refsource_CONFIRM |
| https://github.com/heartcombo/devise/commit/025fe… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| heartcombo | devise |
Affected:
< 5.0.4
|
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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