Vulnerability · Published Sep 23, 2026 · Assigned by GitHub_M
CVE-2026-67238RabbitMQ: Atom-table exhaustion via reply-to queue name decoding
High 7.1
In plain English
A high-severity uncontrolled resource consumption in rabbitmq-server from rabbitmq. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 33% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
RabbitMQ is a messaging and streaming broker. Prior to versions 4.2.7 and 4.3.1, rabbit_pid_codec:decompose_from_binary/1 parses a caller-supplied ETF-encoded binary and calls binary_to_atom(Node, utf8) on the node-name field. It is reached from rabbit_volatile_queue:pid_from_name/2, which is invoked for any queue name / routing key beginning amq.rabbitmq.reply-to.. The CandidateNodes membership check happens after the atom is created, and the surrounding try/catch cannot reclaim atoms (they are never GC'd). binary_to_existing_atom is not used. Any authenticated AMQP client can crash the entire Erlang VM (all vhosts, all connections) with ~1M cheap requests. Preconditions include Authenticated AMQP 0-9-1 connection to any vhost No per-connection rate limit low enough to make ~1M operations infeasible. This issue is fixed in versions 4.2.7 and 4.3.1.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:14 | rabbitmq-server | 4.3.2-1 | DEBIAN-CVE-2026-67238 |
| Ubuntu:22.04:LTS | rabbitmq-server | 3.9.27-0ubuntu0.6 | USN-8933-1 |
| Ubuntu:22.04:LTS | rabbitmq-server | 3.9.27-0ubuntu0.6 | UBUNTU-CVE-2026-67238 |
| Ubuntu:24.04:LTS | rabbitmq-server | 3.12.1-1ubuntu1.7 | UBUNTU-CVE-2026-67238 |
| Ubuntu:24.04:LTS | rabbitmq-server | 3.12.1-1ubuntu1.7 | USN-8933-1 |
| Ubuntu:26.04:LTS | rabbitmq-server | 4.0.5-10ubuntu5.2 | USN-8933-1 |
| Ubuntu:26.04:LTS | rabbitmq-server | 4.0.5-10ubuntu5.2 | UBUNTU-CVE-2026-67238 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| rabbitmq | rabbitmq-server | >= 4.2.0, < 4.2.7>= 4.3.0, < 4.3.1 |
Weakness: CWE-400 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
References
- https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-x96j-244m-mrr2 x_refsource_CONFIRM
- https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.7 x_refsource_MISC
- https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.1 x_refsource_MISC