CVE-2023-25690Public exploitNetwork attack vector

Access-control bypass via rewritten request-target splitting

Published Mar 7, 2023 · Updated Dec 18, 2025

HTTP request smuggling in Apache HTTP Server 2.4.0 through 2.4.55 allows remote attackers to bypass proxy access controls. A permissive RewriteRule or ProxyPassMatch pattern captures untrusted request-target data and substitutes it into the proxied request-target without preventing embedded request delimiters. Exploitation requires mod_proxy and the affected rewrite or proxy configuration, and can route unintended origin requests or poison shared caches.

CVSS severity9.8
Critical
EPSS probability84.51%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

HTTP request smuggling in Apache HTTP Server 2.4.0 through 2.4.55 allows remote attackers to bypass proxy access controls. A permissive RewriteRule or ProxyPassMatch pattern captures untrusted request-target data and substitutes it into the proxied request-target without preventing embedded request delimiters. Exploitation requires mod_proxy and the affected rewrite or proxy configuration, and can route unintended origin requests or poison shared caches.

The record

CVE
CVE-2023-25690
Published
Mar 7, 2023
Updated
Dec 18, 2025
Vendor
The Apache Software Foundation
Product
Apache HTTP Server
Classifications
CWE-444, CAPEC-33, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 7, 2023CVE publishedPublication date reported by the CVE source.
  2. Dec 18, 2025Record 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=2.4.0 <=2.4.55

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Apache Software Foundation · Apache HTTP Serverversion=2.4.0 <=2.4.55

Published CVSS scores

9.8CISACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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-444Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
CAPEC-33HTTP Request Smuggling
T1190Exploit Public-Facing Application

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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