A lack of resource validation in RabbitMQ allows an authenticated user to trigger a cluster-wide denial-of-service condition by allocating excessive memory through malformed routing keys.

This vulnerability, categorized as CWE-770 (Allocation of Resources Without Limits), occurs because the add_binding/3 function fails to enforce an upper bound on the routing key weight. An authenticated user with sufficient permissions can exploit this to force the broker to allocate significant memory on all cluster nodes, resulting in a persistent denial-of-service state.

Successful exploitation results in severe service degradation or complete system downtime across the entire RabbitMQ cluster. Because the malicious binding is persisted to the Khepri record and survives service restarts, the impact is catastrophic for availability and requires manual intervention to clear the offending records. With a CVSS score of 6.0, this represents a significant operational risk to business continuity.

Immediate Action: Upgrade to RabbitMQ versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, or 4.3.0 immediately to implement the required input validation.

Proactive Monitoring: Monitor system memory usage patterns and cluster health logs for spikes in resource consumption following binding operations.

Compensating Controls: Restrict permissions to the consistent-hash exchange plugin to only trusted administrative or service accounts to minimize the attack surface.

Public Exploit Available: Unknown

Organizations utilizing the RabbitMQ consistent-hash exchange plugin must prioritize this update, as the persistent nature of this denial-of-service attack can lead to prolonged outages. Apply the security patches to all cluster nodes simultaneously to ensure consistent resource management and prevent further exploitation.