---
id: "CVE-2026-77412"
kind: "vulnerability"
aliases: ["CVE-2026-77412", "GHSA-4v58-74mf-rjx3", "GO-2026-6494"]
title: "RabbitMQ amqp091-go: Denial of Service via Malicious Field Length in AMQP Client in github.com/rabbitmq/amqp091-go"
severity: "high"
cvss: 8.9
epss: 0.00524
exploited: false
status: "open"
category: "package"
products: [{"name": "github.com/rabbitmq/amqp091-go", "fixed": ["1.13.0"], "affected": "< 1.13.0", "ecosystem": "go"}]
ecosystems: ["go"]
tags: ["amqp", "go", "golang", "package", "rabbitmq"]
not_affected_if: ["fully-trusted-broker", "no-go-client", "version-1.13.0-or-later"]
published_at: "2026-09-16T15:17:50+00:00"
first_seen_at: "2026-10-23T19:13:08+00:00"
updated_at: "2026-10-23T21:43:51+00:00"
sources: [{"source": "govuln", "url": "https://pkg.go.dev/vuln/GO-2026-6494", "first_seen_at": "2026-10-23T19:13:08+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-77412", "first_seen_at": "2026-10-23T19:13:43+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-77412", "first_seen_at": "2026-10-23T19:35:23+00:00"}]
---

# RabbitMQ amqp091-go: Denial of Service via Malicious Field Length in AMQP Client in github.com/rabbitmq/amqp091-go

The amqp091-go Go client for RabbitMQ crashes its whole process when a broker sends a byte-array field with a length of 0xFFFFFFFF, because the length is read as a signed int32 and passed to make. An attacker who controls or compromises the broker can therefore take down any application using the client.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- go:github.com/rabbitmq/amqp091-go affected < 1.13.0 fixed 1.13.0

## How to check

go list -m github.com/rabbitmq/amqp091-go
grep amqp091-go go.mod
Any version below 1.13.0 is affected.

## Fix

Upgrade github.com/rabbitmq/amqp091-go to 1.13.0 or later, then rebuild and redeploy.

## Timeline

- 2026-10-23T19:13:08+00:00 govuln https://pkg.go.dev/vuln/GO-2026-6494
- 2026-10-23T19:13:43+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-77412
- 2026-10-23T19:35:23+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-77412

## From the sources

RabbitMQ amqp091-go is a Go AMQP 0.9.1 client. Prior to 1.13.0, readField in read.go reads the length of an AMQP byte-array field with type tag x into a signed int32 and passes the value directly to make when allocating the field buffer. A malicious or compromised broker can encode a value such as 0xFFFFFFFF, which becomes -1 and causes a len out of range runtime panic. The panic escapes the network reader goroutine and terminates the client process, including during connection.start server properties or message header table parsing. This issue is fixed in version 1.13.0.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_