CVE-2026-33523
Last modified
CVE-2026-33523 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. 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.. EPSS estimates a 0.44% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Apache | Http Server | >= 2.4.0, < 2.4.67 |
References
- https://httpd.apache.org/security/vulnerabilities_24.htmlVendor Advisory
- http://www.openwall.com/lists/oss-security/2026/05/04/23Mailing List, Third Party Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
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