Quick answers
- Is CVE-2026-66067 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-66067 being exploited in the wild.
- How severe is CVE-2026-66067?
- Informational severity, published 23 September 2026.
- Which products and versions are affected?
- RabbitMQ prior to 4.2.7 and 4.3.1.
- Is there a fix for CVE-2026-66067?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-66067 attacked?
- It is attacked over the network, in a hosted service.
- Am I affected by CVE-2026-66067?
- Check whether you run RabbitMQ at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
The stream protocol open handler in RabbitMQ prior to 4.2.7 and 4.3.1 only calls check_vhost_access but omits the per-user and per-vhost connection-limit checks that the AMQP protocol enforces. An authenticated attacker with stream-protocol credentials connecting via port 5552 instead of 5672 can bypass these limits. The vulnerability requires the rabbitmq_stream plugin to be enabled and relies on operators using connection limits for tenant isolation.
Affected products
- RabbitMQ RabbitMQ prior to 4.2.7 and 4.3.1
Timeline
- 2026-09-23: disclosed