CVE-2023-38709: Apache HTTP Server: HTTP response splitting

Severity: high (CVSS 7.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-04-04 · updated 2026-06-17
Weakness: CWE-1284

Description

Faulty input validation in the core of Apache allows malicious or exploitable backend/content generators to split HTTP responses. This issue affects Apache HTTP Server: through 2.4.58.

Affected products

Apache HTTP Server: before 2.4.59 — fixed in 2.4.59
Apple macOS: before 14.6 — fixed in 14.6
Brocade Fabric OS: all versions
Debian Linux: 10.0
Fedoraproject Fedora: 38, 39, 40
NetApp ONTAP 9: 9
NetApp Ontap Tools: 10

How to fix

Upgrade to a fixed version: Apache HTTP Server 2.4.59; Apple macOS 14.6. Check the vendor advisory for mitigations.

References

http://seclists.org/fulldisclosure/2024/Jul/18
http://www.openwall.com/lists/oss-security/2024/04/04/3
https://httpd.apache.org/security/vulnerabilities_24.html
https://lists.debian.org/debian-lts-announce/2024/05/msg00013.html
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/I2N2NZEX3MR64IWSGL3QGN7KSRUGAEMF/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/LX5U34KYGDYPRH3AJ6MDDCBJDWDPXNVJ/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/WNV4SZAPVS43DZWNFU7XBYYOZEZMI4ZC/
https://security.netapp.com/advisory/ntap-20240415-0013/
https://support.apple.com/kb/HT214119
http://seclists.org/fulldisclosure/2024/Jul/18
http://www.openwall.com/lists/oss-security/2024/04/04/3
http://www.openwall.com/lists/oss-security/2025/07/10/2

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