RabbitMQ amqp091-go: Consumer Message Flooding via Signed-to-Unsigned Integer Casting in Qos Configuration (CVE-2026-77406) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-77406

RabbitMQ amqp091-go: Consumer Message Flooding via Signed-to-Unsigned Integer Casting in Qos Configuration

Answer in brief

CVE-2026-77406 records a Unknown severity vulnerability in RabbitMQ amqp091-go: Consumer Message Flooding via Signed-to-Unsigned Integer Casting in Qos Configuration. The current sources do not mark it as known exploited. The current feed maps rabbitmq/amqp091-go (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 16, 2026Updated Sep 16, 2026Source checked Sep 16, 2026First seen by HOL Sep 16, 2026Material review Sep 16, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps rabbitmq/amqp091-go (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
rabbitmq/amqp091-gogeneric	< 1.13.0	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for rabbitmq/amqp091-go.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Sep 16, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 16, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 16, 2026

Sources and claim methodology

Upstream source description

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.

Quoted source text, attributed separately from HOL analysis.