RabbitMQ is a messaging and streaming broker. Prior to versions 4.2.7 and 4.3.1, The stream open handler calls only check_vhost_access; it omits the node/vhost/user connection-limit checks that rabbit_reader performs for AMQP. A developer %% FIXME comment at the cited line explicitly acknowledges the gap. No compensating enforcement exists in connection tracking or elsewhere in rabbitmq_stream. An authenticated tenant can fully bypass operator-configured per-user and per-vhost connection caps by connecting via port 5552 instead of 5672. Preconditions include rabbitmq_stream plugin enabled Authenticated stream-protocol credentials Operator relies on per-user/per-vhost connection limits for tenant isolation. This issue is fixed in versions 4.2.7 and 4.3.1.

rabbitmq-server: RabbitMQ: Unsanitized vhost names allow for XSS in management UI rabbitmq: RabbitMQ: Authenticated user can bypass connection limits via stream protocol rabbitmq: RabbitMQ: Information disclosure of decrypted Shovel URIs in debug logs rabbitmq-server: RabbitMQ: Monitoring user can reset authentication attempt counters rabbitmq-server: RabbitMQ: Cross-Origin Resource Sharing (CORS) misconfiguration allows unauthorized actions rabbitmq-server: RabbitMQ: Denial of Service via atom table exhaustion in stream chunk_selector rabbitmq: RabbitMQ: Denial of Service via management API regular expression filter rabbitmq-server: RabbitMQ: Monitoring user can disrupt message flow via authorization flaw rabbitmq: RabbitMQ: Information disclosure via cross-vhost authorization bypass RabbitMQ: RabbitMQ: Account takeover via stored Cross-Site Scripting in TLS peer-certificate DN rabbitmq-server: RabbitMQ: Denial of Service via AMQP 1.0 array32 parsing rabbitmq-server: RabbitMQ: Denial of Service via unbounded super-stream partition allocation rabbitmq-server: RabbitMQ: Privilege escalation via super-stream HTTP creation rabbitmq: RabbitMQ: Denial of Service via unbounded consistent-hash exchange weight rabbitmq-server: RabbitMQ: Denial of Service via JMS topic exchange atom exhaustion rabbitmq: RabbitMQ: Information disclosure of AMQP 1.0 shovel URI passwords rabbitmq: RabbitMQ: Administrator path traversal allows arbitrary file write rabbitmq: RabbitMQ: Denial of Service vi…

Affected: Ubuntu:Pro:16.04:LTS: rabbitmq-server, Ubuntu:18.04:LTS: rabbitmq-server, Ubuntu:20.04:LTS: rabbitmq-server, Ubuntu:22.04:LTS: rabbitmq-server, Ubuntu:24.04:LTS: rabbitmq-server, Ubuntu:26.04:LTS: rabbitmq-server

RabbitMQ is a messaging and streaming broker. Prior to versions 4.2.7 and 4.3.1, The stream open handler calls only check_vhost_access; it omits the node/vhost/user connection-limit checks that rabbit_reader performs for AMQP. A developer %% FIXME comment at the cited line explicitly acknowledges the gap. No compensating enforcement exists in connection tracking or elsewhere in rabbitmq_stream. An authenticated tenant can fully bypass operator-configured per-user and per-vhost connection caps by connecting via port 5552 instead of 5672. Preconditions include rabbitmq_stream plugin enabled Authenticated stream-protocol credentials Operator relies on per-user/per-vhost connection limits for tenant isolation. This issue is fixed in versions 4.2.7 and 4.3.1.