CVE-2026-57216

Description

RabbitMQ is a messaging and streaming broker. Prior to 3.13.15, 4.0.20, 4.1.11, and 4.2.6, AMQP 0-9-1, AMQP 1.0, and Stream Protocol authentication can allow a loopback-restricted user such as guest to connect remotely when traffic is accepted through a trusted PROXY-protocol path and the backend listener is loopback-bound because the loopback check uses the listener-side socket address instead of the real client source. This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, and 4.2.6.

References

• https://github.com/rabbitmq/rabbitmq-server/commit/7273c9eb6920abcde17b892dbe97ccaf906ead47
• https://github.com/rabbitmq/rabbitmq-server/commit/9f8c39fcf0acbc43080ee7017a62a02832114112
• https://github.com/rabbitmq/rabbitmq-server/pull/15936
• https://github.com/rabbitmq/rabbitmq-server/pull/15940
• https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.6