CVE-2026-77409 RabbitMQ amqp091-go: Denial of Service via Synchronous Event Channel Blocking
An attacker can cause denial of service in RabbitMQ Go clients by triggering event bursts that block the reader goroutine if channels are unbuffered or full.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-77409?
CVE-2026-77409 is a high-severity denial of service vulnerability in rabbitmq amqp091-go, published on 16 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
RabbitMQ amqp091-go is a Go AMQP 0.9.1 client. Prior to 1.13.0, Channel.dispatch in channel.go, confirms.confirm in confirms.go, and Connection.dispatch0 in connection.go synchronously send publisher confirmations, flow-control events, consumer cancellations, returned messages, including NotifyConfirm events and connection block notifications, to application-provided channels. If a listener channel is unbuffered, full, or not drained promptly, the sole reader goroutine blocks and stops processing frames, acknowledgments, deliveries, and heartbeats. Broker-driven event bursts can therefore cause connection stalls, missed heartbeats, deadlocks, and disconnection. This issue is fixed in version 1.13.0.
Weakness: CWE-770
Which versions are affected by CVE-2026-77409?
How do I fix CVE-2026-77409?
Upgrade to a fixed version.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-77409 being exploited?
There is no known exploitation of CVE-2026-77409 in the wild and no public exploit code.
Sources
Also known as AZL-103197, AZL-103281, DEBIAN-CVE-2026-77409, GHSA-wxx3-cj7g-w73j, UBUNTU-CVE-2026-77409.