Medium · published September 24, 2026
RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0, add_vhost/2 calls rabbit_data_coercion:atomize_keys/1 (the unsafe variant using binary_to_atom) on the vhost metadata map. The 20 MB management body limit fits ~1M+ short keys. Admin-only. An administrator importing a crafted definitions file can crash the node in a single request: a vhosts entry with ~1M unique metadata keys exhausts the atom table during import. Preconditions include administrator tag. This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0.
| Product | Versions | Fixed in |
|---|---|---|
| broadcom/rabbitmq_server | ≥ 3.13.0, < 3.13.15 | 3.13.15 |
| broadcom/rabbitmq_server | ≥ 4.0.0, < 4.0.20 | 4.0.20 |
| broadcom/rabbitmq_server | ≥ 4.1.0, < 4.1.11 | 4.1.11 |
| broadcom/rabbitmq_server | ≥ 4.2.0, < 4.2.6 | 4.2.6 |