# CVE-2026-77405: RabbitMQ amqp091-go missing TLS minimum version configuration

Source: https://junglewise.ai/threats/cve-2026-77405-rabbitmq-amqp091-go-missing-tls-minimum-version-configuration  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-16. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-77405 · Severity: critical · CVSS 4 · Published 2026-09-16

RabbitMQ's AMQP client library for Go fails to explicitly set a minimum TLS version when connecting to message brokers. While modern Go compilers default to TLS 1.2, applications built with older Go toolchains (pre-1.18) could fall back to insecure TLS 1.0 or 1.1, allowing attackers to intercept and decrypt sensitive messages and authentication credentials through downgrade attacks.

Technologies: [github.com/rabbitmq/amqp091-go (Go)](https://junglewise.ai/threats/technologies/github-com-rabbitmq-amqp091-go), [RabbitMQ Amqp091-Go](https://junglewise.ai/threats/technologies/amqp091-go). Vendors: [Go](https://junglewise.ai/threats/vendors/go), [RabbitMQ](https://junglewise.ai/threats/vendors/rabbitmq).

## Quick answers

**Is CVE-2026-77405 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-77405 being exploited in the wild.

**How severe is CVE-2026-77405?** Critical severity, with a CVSS score of 4, published 16 September 2026.

**Which products and versions are affected?** github.com/rabbitmq/amqp091-go (Go) < 1.13.0, SEMVER:introduced=0,fixed=1.13.0.

**Is there a fix for CVE-2026-77405?** Yes. github.com/rabbitmq/amqp091-go (Go): upgrade to 1.13.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-77405 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-77405?** Check whether you run github.com/rabbitmq/amqp091-go (Go) or RabbitMQ Amqp091-Go 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.

## How to fix

- github.com/rabbitmq/amqp091-go (Go): upgrade to 1.13.0 or later

  ```sh
  go get github.com/rabbitmq/amqp091-go@v1.13.0
  ```


## Technical details

The vulnerability exists in the `tlsConfigFromURI` function in the AMQP client library, which constructs a `*tls.Config` object without explicitly setting the `MinVersion` field. In Go, an unset `MinVersion` defaults to the toolchain's implicit minimum—TLS 1.0 in pre-1.18 versions. An attacker performing a network-level Man-in-the-Middle attack can force protocol downgrade to TLS 1.0 or 1.1, exposing the connection to known cryptographic attacks (BEAST, POODLE, SWEET32). This affects clients compiled with legacy Go versions or non-standard runtimes. The fix requires explicitly configuring `MinVersion: tls.VersionTLS12` in the TLS configuration builder.

## Affected products

- RabbitMQ amqp091-go

## Identifiers

- CVE-2026-77405
- GHSA-33mj-cw25-m34h
- GO-2026-6492

## Timeline

- 2026-09-17: disclosed

## Related threats

- [amqp091-go pre-negotiation frame limit bypass in connection reader](https://junglewise.ai/threats/cve-2026-107386-amqp091-go-pre-negotiation-frame-limit-is-not-enforced-to-4kb)
- [RabbitMQ amqp091-go denial of service via malicious field length](https://junglewise.ai/threats/cve-2026-77412-rabbitmq-amqp091-go-denial-of-service-via-malicious-field-length)
- [RabbitMQ amqp091-go protocol desynchronization via integer overflow](https://junglewise.ai/threats/cve-2026-77411-rabbitmq-amqp091-go-protocol-desynchronization-via-integer)
- [RabbitMQ amqp091-go resource exhaustion via unbounded buffer allocation](https://junglewise.ai/threats/cve-2026-77410-rabbitmq-amqp091-go-resource-exhaustion-via-unbounded-buffer)
- [RabbitMQ amqp091-go synchronous notification blocking](https://junglewise.ai/threats/cve-2026-77409-rabbitmq-amqp091-go-synchronous-notification-blocking)