CVE-2024-21496Public exploitNetwork attack vector

Session compromise via JavaScript-scheme Referer XSS

Published Feb 17, 2024 · Updated Nov 6, 2024

Cross-site scripting in Greenpau Caddy Security 1.1.23 and earlier allows remote attackers to run JavaScript via a crafted Referer header. Referer handling escapes several HTML metacharacters but fails to reject the javascript URL scheme before returning the value to the browser. A target user must load the affected response for script execution in that user's browser context, exposing the user's session.

CVSS severity5.3
Medium
EPSS probability0.58%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in Greenpau Caddy Security 1.1.23 and earlier allows remote attackers to run JavaScript via a crafted Referer header. Referer handling escapes several HTML metacharacters but fails to reject the javascript URL scheme before returning the value to the browser. A target user must load the affected response for script execution in that user's browser context, exposing the user's session.

The record

CVE
CVE-2024-21496
Published
Feb 17, 2024
Updated
Nov 6, 2024
Vendor
Greenpau
Product
Caddy Security
Classifications
CWE-79, T1189
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 17, 2024CVE publishedPublication date reported by the CVE source.
  2. Nov 6, 2024Record 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

5.3GitHub Advisory DatabaseCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA: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-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1189Drive-by Compromise

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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