Vulnerability-Lookup

GHSA-FC75-39V4-QM5P

Vulnerability from github – Published: 2026-05-04 15:31 – Updated: 2026-05-04 18:30

Details

HTTP response splitting vulnerability in multiple Apache HTTP Server modules with untrusted or compromised backend servers.

This issue affects Apache HTTP Server: from through 2.4.66.

Users are recommended to upgrade to version 2.4.67, which fixes the issue.

Severity ?

6.5 (Medium)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

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JSON

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  },
  "details": "HTTP response splitting vulnerability in multiple Apache HTTP Server modules with untrusted or compromised backend servers.\n\nThis issue affects Apache HTTP Server: from through 2.4.66.\n\nUsers are recommended to upgrade to version 2.4.67, which fixes the issue.",
  "id": "GHSA-fc75-39v4-qm5p",
  "modified": "2026-05-04T18:30:29Z",
  "published": "2026-05-04T15:31:15Z",
  "references": [
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}

CVE-2026-33523 (GCVE-0-2026-33523)

Vulnerability from cvelistv5 – Published: 2026-05-04 14:40 – Updated: 2026-05-04 17:32

Title

Apache HTTP Server: multiple modules: HTTP response splitting forwarding malicious status line

Summary

HTTP response splitting vulnerability in multiple Apache HTTP Server modules with untrusted or compromised backend servers. This issue affects Apache HTTP Server: from through 2.4.66. Users are recommended to upgrade to version 2.4.67, which fixes the issue.

Severity ?

No CVSS data available.

CWE

CWE-443 - HTTP response splitting

Assigner

apache

References

URL

Tags

https://httpd.apache.org/security/vulnerabilities…

vendor-advisory

Impacted products

	Vendor	Product	Version
	Apache Software Foundation	Apache HTTP Server	Affected: 2.4.0 , ≤ 2.4.66 (semver)

Credits

Haruki Oyama (Waseda University) Merih Mengisteab Dawit Jeong

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JSON

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              "confidentialityImpact": "LOW",
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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-FC75-39V4-QM5P

CVE-2026-33523 (GCVE-0-2026-33523)

Tags

Sightings

Nomenclature