CVE-2026-28780
Apache HTTP Server: buffer overflow in mod_proxy_ajp via ajp_msg_check_header()
9.8
CRITICAL
CVSS 3.1
EPSS 0.02%
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.
How to fix CVE-2026-28780
To remediate CVE-2026-28780, upgrade the affected package to a fixed version below.
- —upgrade to 2.4.67-r0 or later
- —upgrade to 2.4.67 or later
- —upgrade to 2.4.67-1~deb11u1 or later
Is CVE-2026-28780 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (3)
- from 0, < 2.4.67-r0
- from 0, < 2.4.67
- from 0, < 2.4.67-1~deb11u1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | CRITICAL9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |