CVE-2026-66072 RabbitMQ: Atom table exhaustion via stream `chunk_selector`
An authenticated user can crash the RabbitMQ broker by exhausting atom tables via stream chunk selectors, requiring the stream plugin to be enabled.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-66072?
CVE-2026-66072 is a medium-severity denial of service vulnerability in Broadcom Rabbitmq Server, published on 23 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.1, get_chunk_selector/1 calls binary_to_atom on the raw client-supplied <<"chunk_selector">> property from post-auth subscribe and resolve_offset_spec frames, with no whitelist and no existing guard. An authenticated stream client with read access to any stream can crash the broker node. Preconditions include rabbitmq_stream plugin enabled Authenticated stream-protocol user with read access to at least one stream. This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.1.
Weakness: CWE-400
Which versions are affected by CVE-2026-66072?
1 open source package ship an affected version, including rabbitmq. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
rabbitmq Bitnami | From 3.13.0 | 3.13.15, 4.0.20, 4.1.11, 4.2.6, 4.3.1 |
Products include Broadcom Rabbitmq Server.
How do I fix CVE-2026-66072?
Upgrade rabbitmq to a fixed version for your release line: 3.13.15, 4.0.20, 4.1.11 or 4.2.6.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-66072 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-66072 exists.
Other vulnerabilities in Broadcom Rabbitmq Server
- CVE-2016-9877 Auth bypass in Pivotal RabbitMQ 3.x before 3.5.8 and 3.6.x before 3.6.6; RabbitMQ for PCF 1.5.x before 1.5.20, 1.6.x before 1.6.12 and 1.7.x before 1.7.7
- CVE-2026-67404 RabbitMQ: OAuth2 silent verify_none fallback for JWKS fetch
- CVE-2026-67231 RabbitMQ: Trust-store whitelist by Issuer+Serial only
- CVE-2026-57219 Information disclosure in rabbitmq-server
- CVE-2026-67236 RabbitMQ: Plaintext username:password stored in an insecure cookie after successful POST /login
Sources
Also known as AZL-105786, BIT-rabbitmq-2026-66072, DEBIAN-CVE-2026-66072, GHSA-48hm-chgv-398r, UBUNTU-CVE-2026-66072.