CVE-2025-49630

Name	CVE-2025-49630
Description	In certain proxy configurations, a denial of service attack against Apache HTTP Server versions 2.4.26 through to 2.4.63 can be triggered by untrusted clients causing an assertion in mod_proxy_http2. Configurations affected are a reverse proxy is configured for an HTTP/2 backend, with ProxyPreserveHost set to "on".
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

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)	2.4.62-1~deb11u2	vulnerable
	bookworm, bookworm (security)	2.4.62-1~deb12u2	vulnerable
	trixie	2.4.63-1	vulnerable
	sid	2.4.64-1	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
apache2	source	(unstable)	2.4.64-1

https://httpd.apache.org/security/vulnerabilities_24.html#CVE-2025-49630