Microsoft MCP Gateway privilege elevation via user-controlled key

high severity · published 2026-11-10

An authorized attacker can bypass authorization in MCP Gateway through a user-controlled key and elevate privileges over the network. This can lead to unauthorized access to gateway resources.

Fixed in: 1.0.0

CVE: CVE-2026-109492

Source: NVD

Am I affected?

You are affected if the installed version is older than 1.0.0. Check the version you have and update to 1.0.0 or later. The fixed version is verified against a vendor or advisory source.

Get the fix

FixLane has a reviewed fix procedure for this incident: a read-only check first, then the fix. Ask the Telegram bot, or connect an AI agent to the FixLane MCP server and call get_fix_prompt with incident id 2397 and your operating system.