CVE-2026-28780: Apache HTTP Server: buffer overflow in mod_proxy_ajp via ajp_msg_check_header()

Published May 5, 2026
·
Updated

Heap-based Buffer Overflow vulnerability in modproxyajp of Apache HTTP Server. If modproxyajp connects to a malicious AJP server this AJP server can send a malicious AJP message back to modproxyajp and cause it to write 4 attacker controlled bytes after the end of a heap based buffer.

This issue affects Apache HTTP Server: through 2.4.66.

Users are recommended to upgrade to version 2.4.67, which fixes the issue.

Affected Software

2 affected components
Apache HTTP Server<=2.4.66
Apache HTTP Server<2.4.67

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Apache HTTP Server to a version that resolves this vulnerability.

    Fixed in 2.4.67Patch CVE-2026-28780

Event History

May 5, 2026
CVE Published
via MITRE·09:29 PM
Data Sourced
via MITRE·09:29 PM
DescriptionWeakness
Data Sourced
via Red Hat·10:01 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·10:16 PM
DescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2026-28780?

CVE-2026-28780 is classified as a high severity vulnerability due to its potential for a buffer overflow exploit.

2

How do I fix CVE-2026-28780?

To fix CVE-2026-28780, update your Apache HTTP Server to version 2.4.67 or later.

3

What causes CVE-2026-28780?

CVE-2026-28780 is caused by a heap-based buffer overflow in the mod_proxy_ajp module when connected to a malicious AJP server.

4

Who is affected by CVE-2026-28780?

CVE-2026-28780 affects users of Apache HTTP Server versions up to 2.4.66 that utilize the mod_proxy_ajp module.

5

What are the potential consequences of CVE-2026-28780?

Exploitation of CVE-2026-28780 could lead to remote code execution or denial of service on affected systems.

Contact

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