CVE-2026-33523 - Vulnerability Details - OpenCVE

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.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact Low

Integrity Impact Low

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable yes

Technical Impact partial

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References

Link	Providers
https://httpd.apache.org/security/vulnerabilities_24.html

History

Mon, 04 May 2026 16:15:00 +0000

Type	Values Removed	Values Added
Metrics		cvssV3_1 `{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N'}` ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Mon, 04 May 2026 15:00:00 +0000

Type	Values Removed	Values Added
Description		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.
Title		Apache HTTP Server: multiple modules: HTTP response splitting forwarding malicious status line
Weaknesses		CWE-443
References		https://httpd.apache.org/security/vulnerabilities_24.html

MITRE

Status: PUBLISHED

Assigner: apache

Published: 2026-05-04T14:40:41.430Z

Updated: 2026-05-04T15:56:35.673Z

Reserved: 2026-03-20T17:29:39.696Z

Link: CVE-2026-33523

Vulnrichment

Updated: 2026-05-04T15:55:21.968Z

NVD

Status : Undergoing Analysis

Published: 2026-05-04T15:16:04.227

Modified: 2026-05-04T15:21:58.203

Link: CVE-2026-33523

Redhat

No data.

OpenCVE Enrichment

No data.

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