CVE-2024-45403

Name	CVE-2024-45403
Description	h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. When h2o is configured as a reverse proxy and HTTP/3 requests are cancelled by the client, h2o might crash due to an assertion failure. The crash can be exploited by an attacker to mount a Denial-of-Service attack. By default, the h2o standalone server automatically restarts, minimizing the impact. However, HTTP requests that were served concurrently will still be disrupted. The vulnerability has been addressed in commit 1ed32b2. Users may disable the use of HTTP/3 to mitigate the issue.
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
h2o (PTS)	buster (security), buster, buster (lts)	2.2.5+dfsg2-2+deb10u2	vulnerable
	bullseye	2.2.5+dfsg2-6	fixed
	bookworm	2.2.5+dfsg2-7	fixed
	sid, trixie	2.2.5+dfsg2-9	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
h2o	source	buster	(unfixed)	end-of-life
h2o	source	(unstable)	(not affected)

Notes

- h2o <not-affected> (Vulnerable code introduced later)
https://github.com/h2o/h2o/security/advisories/GHSA-4xp5-3jhc-3m92
Introduced by: https://github.com/h2o/h2o/commit/16b13eee8ad7895b4fe3fcbcabee53bd52782562
Fixed by: https://github.com/h2o/h2o/commit/1ed32b23f999acf0c5029f09c8525f93eb1d354c