Is CVE-2026-125926 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-125926 being exploited in the wild.

How severe is CVE-2026-125926?

High severity, with a CVSS score of 8.5, published 11 November 2026.

Which products and versions are affected?

Amazon Mcp-Gateway-Registry v1.0.3 through 1.34.0.

How is CVE-2026-125926 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-125926?

Check whether you run Amazon AWS or Amazon Mcp-Gateway-Registry at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-125926: Amazon mcp-gateway-registry server-side request forgery in registration API

CVE-2026-125926 · Severity: high · CVSS 8.5 · Published 2026-11-11

mcp-gateway-registry is a registry and gateway for Model Context Protocol servers that enables discovery and access control of MCP tools. An authenticated attacker with permission to register or modify servers can configure malicious upstream addresses to cause the gateway to make requests to internal network services and cloud metadata endpoints, potentially exposing sensitive information like credentials. This vulnerability allows lateral movement within networks and access to cloud instance metadata.

Technologies: Amazon AWS, Amazon Mcp-Gateway-Registry. Vendors: Amazon.

Quick answers

Is CVE-2026-125926 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-125926 being exploited in the wild.
How severe is CVE-2026-125926?: High severity, with a CVSS score of 8.5, published 11 November 2026.
Which products and versions are affected?: Amazon Mcp-Gateway-Registry v1.0.3 through 1.34.0.
Is there a fix for CVE-2026-125926?: Yes: fixed in mcp-gateway-registry 1.35.0. Until then: Limit the permission to register and modify servers to trusted accounts only. Restrict outbound network access from the registry and auth-server components to only required destinations. Require IMDSv2 on Amazon EC2 and grant roles only minimum necessary permissions. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-125926 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-125926?: Check whether you run Amazon AWS or Amazon Mcp-Gateway-Registry at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Fixed in: mcp-gateway-registry 1.35.0

Limit the permission to register and modify servers to trusted accounts only. Restrict outbound network access from the registry and auth-server components to only required destinations. Require IMDSv2 on Amazon EC2 and grant roles only minimum necessary permissions.

Technical details

Server-side request forgery (SSRF) in the server registration and update API fails to properly validate upstream addresses. An authenticated user with server registration/modification permissions can craft a request with a malicious upstream address to force the gateway to send requests to internal services or cloud metadata endpoints. The gateway may return responses to the attacker, enabling information disclosure.

Affected products

Amazon mcp-gateway-registry v1.0.3 through 1.34.0

Timeline

2026-11-11: disclosed
2026-11-11: patched: Fixed in version 1.35.0

References

https://aws.amazon.com/security/security-bulletins/rss/2026-180-aws/

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