CVE-2026-66073 is a vulnerability in RabbitMQ server versions prior to 3.9.23-5.oe2403sp1 and certain 3.13.x and 4.x versions, involving atom table exhaustion via the management API node field. This flaw allows any user with management tag and one vhost to cause a denial of service by crashing the Erlang VM after roughly 900,000 crafted requests. The issue arises because unique node values are converted to atoms without proper cluster membership checks, leading to permanent atom leaks. The vulnerability is fixed in RabbitMQ versions 3.9.23-5.oe2403sp1, 3.13.15, 4.0.20, 4.1.11, and 4.2.6.