CVE-2026-77408: Rabbitmq AMQP091-Go

Critical severity, CVSS 9.1. EPSS: 0.5% chance of exploitation in the next 30 days.

RabbitMQ amqp091-go is a Go AMQP 0.9.1 client. Prior to 1.13.0, the writeShortstr function in write.go casts the byte length of AMQP shortstr property values to uint8 without first rejecting values longer than 255 bytes. An application that accepts an oversized CorrelationId, ReplyTo, MessageId, Expiration, UserId, AppId, ContentType, ContentEncoding, or Type value can therefore serialize a wrapped length and only a truncated prefix, while reporting no error. The resulting silent metadata corruption can break request and reply correlation, routing, tracing, and downstream message processing. This issue is fixed in version 1.13.0.

Affected products

• Rabbitmq AMQP091-Go: before 1.13.0 (fixed in 1.13.0)

Published 2026-09-16. Last modified 2026-09-23.