CVE-2026-67226

Name	CVE-2026-67226
Description	RabbitMQ is a messaging and streaming broker. From 4.0.0 until 4.0.22 and 4.1.14 and 4.2.7, Admin-only atom exhaustion: PUT /api/users tags list. settags/2 maps rabbitdatacoercion:toatom/1 over the user's tags list. The 20 MB management body limit fits ~3-4M short tag strings. An administrator can crash the node in a single request by creating a user (or importing definitions) with ~1M unique tag administrator. This issue is fixed in versions 4.0.22 and 4.1.14 and 4.2.7.
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)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
rabbitmq-server (PTS)	bookworm, bookworm (security)	3.10.8-1.1+deb12u1	vulnerable
	trixie	4.0.5-6+deb13u2	vulnerable
	forky	4.3.2-4	vulnerable
	sid	4.3.2-5	vulnerable

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
rabbitmq-server	source	(unstable)	(unfixed)

https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-34c7-r8w9-5wv8