CVE-2026-33523: CWE-443: HTTP response splitting in Apache Software Foundation Apache HTTP Server
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.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-33523) involves HTTP response splitting in several Apache HTTP Server modules when processing responses from untrusted or compromised backend servers. It affects Apache HTTP Server versions from 2.4.0 up to and including 2.4.66. The vulnerability allows an attacker to manipulate HTTP responses, potentially leading to security issues such as cache poisoning or cross-site scripting, though specific impacts are not detailed in the provided data. The Apache Software Foundation has fixed this issue in version 2.4.67.
Potential Impact
The vulnerability could allow attackers to perform HTTP response splitting attacks via compromised or untrusted backend servers, potentially leading to security issues such as cache poisoning or injection of malicious content in HTTP responses. However, no known exploits are reported in the wild as of the published date. The impact is limited to affected Apache HTTP Server versions prior to 2.4.67.
Mitigation Recommendations
Users should upgrade Apache HTTP Server to version 2.4.67 or later, where this vulnerability is fixed. No other mitigation guidance is provided. Patch status is confirmed by the vendor advisory recommending this upgrade.
CVE-2026-33523: CWE-443: HTTP response splitting in Apache Software Foundation Apache HTTP Server
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.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-33523) involves HTTP response splitting in several Apache HTTP Server modules when processing responses from untrusted or compromised backend servers. It affects Apache HTTP Server versions from 2.4.0 up to and including 2.4.66. The vulnerability allows an attacker to manipulate HTTP responses, potentially leading to security issues such as cache poisoning or cross-site scripting, though specific impacts are not detailed in the provided data. The Apache Software Foundation has fixed this issue in version 2.4.67.
Potential Impact
The vulnerability could allow attackers to perform HTTP response splitting attacks via compromised or untrusted backend servers, potentially leading to security issues such as cache poisoning or injection of malicious content in HTTP responses. However, no known exploits are reported in the wild as of the published date. The impact is limited to affected Apache HTTP Server versions prior to 2.4.67.
Mitigation Recommendations
Users should upgrade Apache HTTP Server to version 2.4.67 or later, where this vulnerability is fixed. No other mitigation guidance is provided. Patch status is confirmed by the vendor advisory recommending this upgrade.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- apache
- Date Reserved
- 2026-03-20T17:29:39.696Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69f8b5f1cbff5d86102f7019
Added to database: 5/4/2026, 3:06:25 PM
Last enriched: 5/4/2026, 3:21:45 PM
Last updated: 5/4/2026, 4:45:10 PM
Views: 3
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