🟠 High | Source: Microsoft Security Response Center
A vulnerability in RabbitMQ’s stream listener allows unauthenticated attackers to send oversized frames during the authentication handshake, bypassing the configured frame-size limit. This can exhaust server memory, causing a denial-of-service condition without any credentials being required. The flaw is particularly concerning because it can be triggered before any authentication takes place, lowering the bar for exploitation significantly.
Security Architect’s Take: Review any Azure-hosted or Azure-integrated RabbitMQ deployments — particularly those exposing the stream protocol port (5552) — and apply vendor patches immediately. As an interim control, restrict network access to the RabbitMQ stream listener to trusted IP ranges only, using NSGs or equivalent perimeter controls.
Original advisory: CVE-2026-57220 RabbitMQ: Stream listener does not enforce configured frame-size limit during authentication, permitting unauth’d mem-exhaust DoS