CVE-2024-40898Network attack vector

NTLM hash disclosure via rewritten UNC paths

Published Jul 18, 2024 · Updated Sep 13, 2024

SSRF in mod_rewrite in Apache HTTP Server 2.4.0 through 2.4.61 on Windows allows remote attackers to disclose NTLM hashes. In server or virtual-host context, a request-derived rewrite substitution can resolve as a Windows UNC path and trigger outbound SMB authentication. The server must run on Windows with applicable mod_rewrite rules; Linux and macOS deployments are outside the affected scope.

CVSS severity7.5
High
EPSS probability1.54%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

SSRF in mod_rewrite in Apache HTTP Server 2.4.0 through 2.4.61 on Windows allows remote attackers to disclose NTLM hashes. In server or virtual-host context, a request-derived rewrite substitution can resolve as a Windows UNC path and trigger outbound SMB authentication. The server must run on Windows with applicable mod_rewrite rules; Linux and macOS deployments are outside the affected scope.

The record

CVE
CVE-2024-40898
Published
Jul 18, 2024
Updated
Sep 13, 2024
Vendor
The Apache Software Foundation
Product
Apache HTTP Server
Classifications
CWE-918, T1187
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 18, 2024CVE publishedPublication date reported by the CVE source.
  2. Sep 13, 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=2.4.0 <=2.4.61

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Apache Software Foundation · Apache HTTP Serverversion=2.4.0 <=2.4.61

Published CVSS scores

9.1CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/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-918Server-Side Request Forgery (SSRF)
T1187Forced Authentication

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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