CVE-2026-33523

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://httpd.apache.org/security/vulnerabilities_24.html	Vendor Advisory
http://www.openwall.com/lists/oss-security/2026/05/04/23	Mailing List Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-04 15:16

Updated : 2026-06-17 10:37

NVD link : CVE-2026-33523

Mitre link : CVE-2026-33523

CVE.ORG link : CVE-2026-33523

JSON object : View

Products Affected

apache

http_server

CWE

CWE-443

DEPRECATED: HTTP response splitting

NVD-CWE-Other

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