CVE-2026-28780

Name	CVE-2026-28780
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.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
References	DLA-4571-1, DSA-6248-1

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
apache2 (PTS)	bullseye	2.4.62-1~deb11u1	vulnerable
	bullseye (security)	2.4.67-1~deb11u1	fixed
	bookworm, bookworm (security)	2.4.67-1~deb12u2	fixed
	trixie (security), trixie	2.4.67-1~deb13u2	fixed
	forky, sid	2.4.67-1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Origin
apache2	source	bullseye	2.4.67-1~deb11u1	DLA-4571-1
apache2	source	bookworm	2.4.67-1~deb12u2	DSA-6248-1
apache2	source	trixie	2.4.67-1~deb13u2	DSA-6248-1
apache2	source	(unstable)	2.4.67-1

Notes

https://httpd.apache.org/security/vulnerabilities_24.html#CVE-2026-28780
https://github.com/apache/httpd/commit/d04119e6e591f7b21222e749387a8b39e9092a1b (2.4.67-rc1-candidate)