6.5
MEDIUM CVSS 4.0
CVE-2026-18655
Broker Credential and OAuth Token Disclosure in AWS Labs Amazon MQ MCP Server via Prompt Injection
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.

INFO

Published Date :

Aug. 3, 2026, 8:17 p.m.

Last Modified :

Aug. 3, 2026, 8:17 p.m.

Remotely Exploit :

Yes !

Source :

ff89ba41-3aa1-4d27-914a-91399e9639e5
Affected Products

The following products are affected by CVE-2026-18655 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Aws amazon-mq-mcp-server
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 MEDIUM ff89ba41-3aa1-4d27-914a-91399e9639e5
CVSS 3.1 MEDIUM MITRE-CVE
CVSS 4.0 HIGH ff89ba41-3aa1-4d27-914a-91399e9639e5
CVSS 4.0 HIGH ff89ba41-3aa1-4d27-914a-91399e9639e5
Solution
Upgrade Amazon MQ MCP Server to version 2.0.24 to fix endpoint restriction vulnerability.
  • Upgrade Amazon MQ MCP Server to version 2.0.24.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-18655.

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

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-18655 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-18655 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-18655 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-18655 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by ff89ba41-3aa1-4d27-914a-91399e9639e5

    Aug. 03, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'AWS', 'product': 'amazon-mq-mcp-server', 'versions': [{'status': 'affected', 'version': '0', 'versionType': 'custom', 'lessThanOrEqual': '2.0.23'}], 'defaultStatus': 'unaffected'}]
    Added 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.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
    Added CWE CWE-923
    Added Reference https://aws.amazon.com/security/security-bulletins/2026-070-aws/
    Added Reference https://github.com/awslabs/mcp/security/advisories/GHSA-xwj6-8x5h-hjp6
    Added Reference https://pypi.org/project/awslabs.amazon-mq-mcp-server/2.0.24/
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Aug. 03, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-18655', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-08-03T19:52:05.730514Z'}
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.