CVE-2026-40295Network attack vector

Open redirect via unvalidated non-GET timeout Referer

Published May 22, 2026 · Updated May 22, 2026

Open redirect in heartcombo Devise 5.0.3 and earlier allows remote attackers to redirect expired-session users via non-GET requests. FailureApp#redirect_url passes the attacker-controlled HTTP Referer directly to redirect_to instead of stripping its external host. Exploitation requires Timeoutable, an expired victim session, and a crafted link or auto-submitting cross-origin form, enabling phishing or malware delivery through the trusted application domain.

CVSS severity6.1
Medium
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Open redirect in heartcombo Devise 5.0.3 and earlier allows remote attackers to redirect expired-session users via non-GET requests. FailureApp#redirect_url passes the attacker-controlled HTTP Referer directly to redirect_to instead of stripping its external host. Exploitation requires Timeoutable, an expired victim session, and a crafted link or auto-submitting cross-origin form, enabling phishing or malware delivery through the trusted application domain.

The record

CVE
CVE-2026-40295
Published
May 22, 2026
Updated
May 22, 2026
Vendor
heartcombo
Product
Devise
Classifications
CWE-601, T1189
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 22, 2026CVE publishedPublication date reported by the CVE source.
  2. May 22, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 5.0.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

heartcombo · Deviseversion=< 5.0.4

Published CVSS scores

6.1GitHubCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-601URL Redirection to Untrusted Site ('Open Redirect')
T1189Drive-by Compromise

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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