GHSA-33mj-cw25-m34h: github.com/rabbitmq/amqp091-go (CVE-2026-77405)

Package	Ecosystem	Affected	Fixed in
github.com/rabbitmq/amqp091-go	Go	<1.13.0	1.13.0

Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

The amqp091-go library for Go, versions before 1.13.0, does not explicitly set a minimum TLS version when building the TLS configuration from amqps:// URIs, so it relies on the Go toolchain default. An attacker able to perform a man-in-the-middle attack could force a downgrade to TLS 1.0 or 1.1 when the client was built with a Go version earlier than 1.18, exposing message data and credentials. Upgrade to version 1.13.0 or later, which is the listed fixed version.

Written 1 Nov 2026.

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
9.4	Critical	4.0	CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:H/SI:L/SA:N	CNA (GitHub_M)

CISA KEV Not listed.
EPSS 0.0028, the 20th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

31 Oct 2026, 14:12 UTC First seen by agentprime
31 Oct 2026, 14:12 UTC Confirmed by OSV

Sources

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.