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

Publication date: 2026-06-08

Last updated on: 2026-06-08

Assigner: Apache Software Foundation

Description
Heap-based Buffer Overflow vulnerability in Apache HTTP Server with malicious backend servers and ProxyPassReverseCookie* This issue affects Apache HTTP Server: from 2.4.0 through 2.4.67. Users are recommended to upgrade to version 2.4.68, which fixes the issue.
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Meta Information
Published
2026-06-08
Last Modified
2026-06-08
Generated
2026-06-09
AI Q&A
2026-06-08
EPSS Evaluated
N/A
NVD
CVE-2026-34356
EUVD
EUVD-2026-35089
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
apache http_server From 2.4.0 (inc) to 2.4.67 (inc)
Helpful Resources
Exploitability
CWE
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KEV
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CWE ID Description
CWE-122 A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().
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Executive Summary

This vulnerability is a heap-based buffer overflow in the Apache HTTP Server. It occurs when the server interacts with malicious backend servers and involves the ProxyPassReverseCookie* functionality.

The issue affects Apache HTTP Server versions from 2.4.0 through 2.4.67.

Users are advised to upgrade to version 2.4.68, which contains the fix for this vulnerability.

Impact Analysis

A heap-based buffer overflow can allow an attacker to execute arbitrary code, cause a denial of service, or crash the Apache HTTP Server.

Since the vulnerability involves malicious backend servers and ProxyPassReverseCookie*, an attacker controlling a backend server could exploit this to compromise the front-end Apache server.

This could lead to unauthorized access, data corruption, or service disruption.

Mitigation Strategies

Users are recommended to upgrade Apache HTTP Server to version 2.4.68, which fixes the heap-based buffer overflow vulnerability.

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