CVE-2026-33523

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Source
https://cve.org/CVERecord?id=CVE-2026-33523
Import Source
https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-33523.json
JSON Data
https://api.test.osv.dev/v1/vulns/CVE-2026-33523
Aliases
Downstream
Published
2026-05-04T14:40:41.430Z
Modified
2026-05-10T11:50:49.621675Z
Severity
  • 6.5 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N CVSS Calculator
Summary
Apache HTTP Server: multiple modules: HTTP response splitting forwarding malicious status line
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.

Database specific 
{
    "unresolved_ranges": [
        {
            "source": "AFFECTED_FIELD",
            "extracted_events": [
                {
                    "introduced": "2.4.0"
                },
                {
                    "last_affected": "2.4.66"
                }
            ]
        },
        {
            "source": "DESCRIPTION",
            "extracted_events": [
                {
                    "fixed": "2.4.66"
                }
            ]
        }
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33523.json",
    "cna_assigner": "apache",
    "cwe_ids": [
        "CWE-443"
    ]
}
References

Affected packages

Git / github.com/apache/httpd

Affected ranges

Type
GIT
Repo
https://github.com/apache/httpd
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
e4a77ef6051b3fe22eafacbcf54855b178a0bddd
Database specific 
{
    "source": "DESCRIPTION",
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "2.4.66"
        }
    ]
}

Affected versions

2.*
2.4.66-rc1-candidate

Database specific

source 
"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-33523.json"