CVE-2026-28780

Name: CVE-2026-28780
Creator: NVD / NIST
Published: 2026-05-05T22:16:00.39+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 0.72%

Last modified Jun 17, 2026

CVE-2026-28780 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. Heap-based Buffer Overflow vulnerability in mod_proxy_ajp of Apache HTTP Server. If mod_proxy_ajp connects to a malicious AJP server this AJP server can send a malicious AJP message back to mod_proxy_ajp 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.. EPSS estimates a 0.72% chance of exploitation in the next 30 days.

Description

Heap-based Buffer Overflow vulnerability in mod_proxy_ajp of Apache HTTP Server. If mod_proxy_ajp connects to a malicious AJP server this AJP server can send a malicious AJP message back to mod_proxy_ajp 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.

Metrics

CVSS 3.1

9.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

0.72%

49.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-122

Affected Software

Vendor	Product	Versions
Apache	Http Server	< 2.4.67

References

https://httpd.apache.org/security/vulnerabilities_24.htmlRelease Notes, Vendor Advisory
http://www.openwall.com/lists/oss-security/2026/05/05/9Mailing List, Third Party Advisory

Timeline

Published: May 5, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-28780?

How severe is CVE-2026-28780?

CVE-2026-28780 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 0.72% probability of exploitation in the next 30 days.

How do I fix CVE-2026-28780?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-28780?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST