CVE-2024-21497Public exploitNetwork attack vector

Phishing via unvalidated login redirect destination

Published Feb 17, 2024 · Updated Mar 3, 2026

Open redirect in Greenpau Caddy Security before 1.1.36 allows remote attackers to send users to external sites via crafted redirect_url values. The authentication portal accepts redirect_url as a login destination and redirects to it without restricting the destination to the same domain or a trusted source. No prior attacker access is required, but a logged-in user must follow the crafted link and click a portal button or use the browser's back button, enabling phishing.

CVSS severity6.1
Medium
EPSS probability0.50%
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 Greenpau Caddy Security before 1.1.36 allows remote attackers to send users to external sites via crafted redirect_url values. The authentication portal accepts redirect_url as a login destination and redirects to it without restricting the destination to the same domain or a trusted source. No prior attacker access is required, but a logged-in user must follow the crafted link and click a portal button or use the browser's back button, enabling phishing.

The record

CVE
CVE-2024-21497
Published
Feb 17, 2024
Updated
Mar 3, 2026
Vendor
Greenpau
Product
Caddy Security
Classifications
CWE-601, T1566.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 17, 2024CVE publishedPublication date reported by the CVE source.
  2. Mar 3, 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=0 <*

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Greenpau · Caddy Securityversion=0 <*

Published CVSS scores

5.4SnykCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
6.1NVDCVSS: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 exploitPublished

Weakness, pattern, technique

CWE-601URL Redirection to Untrusted Site ('Open Redirect')
T1566.002Spearphishing Link

Public exploit references

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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