---
id: CVE-2026-77406
title: RabbitMQ amqp091-go is a Go AMQP 0.9.1 client
summary: >-
  RabbitMQ amqp091-go is a Go AMQP 0.9.1 client. Prior to 1.13.0, Channel.Qos in
  channel.go accepts negative prefetchCount and prefetchSize integers and casts
  them directly to uint16 and uint32 fields in the basic.qos method because
  valida…
severity: high
cvss: 8.2
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L'
cwe:
  - CWE-195
  - CWE-190
vendor: rabbitmq
product: amqp091-go
affected:
  - amqp091-go < 1.13.0
patched:
  - github.com/rabbitmq/amqp091-go 1.13.0
published: '2026-09-16'
updated: '2026-09-23'
sourceUpdated: '2026-09-23T18:19:19.803'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-77406'
references:
  - url: >-
      https://github.com/rabbitmq/amqp091-go/commit/3b879e1d1d25b544e26b3bc3d7db3213203c0f3b
    label: security-advisories@github.com
  - url: 'https://github.com/rabbitmq/amqp091-go/pull/351'
    label: security-advisories@github.com
  - url: 'https://github.com/rabbitmq/amqp091-go/releases/tag/v1.13.0'
    label: security-advisories@github.com
  - url: >-
      https://github.com/rabbitmq/amqp091-go/security/advisories/GHSA-rm6m-hrcw-jw33
    label: security-advisories@github.com
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-77406'
  - url: 'https://github.com/advisories/GHSA-rm6m-hrcw-jw33'
  - url: 'https://github.com/rabbitmq/amqp091-go'
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-77406.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-77406'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2535493'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-77406'
  - url: 'https://access.redhat.com/errata/RHSA-2026:68290'
tags:
  - nvd
  - cve.org
  - ghsa
  - go
  - osv
  - csaf
  - vex
  - red-hat
epss: 0.00412
epssPercentile: 0.32604
aliases:
  - GHSA-rm6m-hrcw-jw33
ecosystem: go
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-16T18:18:39.588892Z'
cvssSource: cna
scores:
  cna: 8.2
  vendor: 7.5
ingestedAt: '2026-09-16T14:57:28.049Z'
---

## Overview

RabbitMQ amqp091-go is a Go AMQP 0.9.1 client. Prior to 1.13.0, Channel.Qos in channel.go accepts negative prefetchCount and prefetchSize integers and casts them directly to uint16 and uint32 fields in the basic.qos method because validateQos is absent. Values such as -1 therefore wrap to 65535 or 4294967295 instead of being rejected. An application that permits untrusted configuration of these Qos values can unintentionally request extremely large prefetch limits, allowing a broker to deliver enough queued messages to exhaust client memory and disrupt processing. This issue is fixed in version 1.13.0.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-77406)

Affected packages:

- `github.com/rabbitmq/amqp091-go < 1.13.0`

Patched in:

- `github.com/rabbitmq/amqp091-go 1.13.0`

Source: https://github.com/advisories/GHSA-rm6m-hrcw-jw33

## Vendor advisories

- **Red Hat VEX** · Important · affected: Cryostat 4, Multicluster Global Hub, OpenShift Serverless, Red Hat Advanced Cluster Management for Kubernetes 2, Red Hat OpenStack Platform 18.0, Red Hat Quay 3 · no fix planned: Cryostat 4, Multicluster Global Hub, OpenShift Serverless, Red Hat Advanced Cluster Management for Kubernetes 2, … · updated 2026-09-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-77406.json)
- **RHSA-2026:68290** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-09-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:68290)