Heap-based Buffer Overflow in Apache HTTP Server Products
CVE-2026-34356

7.5HIGH

Key Information:

Vendor

Apache
Status
Apache Http Server
Vendor
CVE Published:
8 June 2026

What is CVE-2026-34356?

A heap-based buffer overflow vulnerability exists in the Apache HTTP Server, potentially allowing an attacker exploiting malicious backend servers to execute arbitrary code through the ProxyPassReverseCookie directive. This affects versions from 2.4.0 up to 2.4.67 and requires immediate attention by upgrading to version 2.4.68, which addresses this critical security flaw.

Affected Version(s)

Apache HTTP Server 2.4.0 <= 2.4.67

References

https://httpd.apache.org/security/vulnerabilities_24.html
vendor-advisory

CVSS V3.1

Score:
7.5
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Arkadi Vainbrand
depthfirst (depthfirst.com)
.