---
id: "CVE-2026-102610"
page: "https://infrastack.ai/live/CVE-2026-102610"
kind: "vulnerability"
aliases: ["CVE-2026-102610"]
title: "fast-agent: unauthenticated MCP server can run OS commands remotely"
severity: "medium"
cvss: 6.4
epss: null
exploited: false
status: "open"
category: "ai-tooling"
products: []
ecosystems: []
tags: ["ai-tooling", "mcp", "python", "self-hosted"]
not_affected_if: ["auth-proxy", "fixed-version", "localhost-only"]
published_at: "2026-11-06T21:17:05+00:00"
first_seen_at: "2026-11-06T21:45:07+00:00"
updated_at: "2026-11-06T21:46:44+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-102610", "first_seen_at": "2026-11-06T21:45:07+00:00"}]
exploit_sources: []
---

# fast-agent: unauthenticated MCP server can run OS commands remotely

Link for people: https://infrastack.ai/live/CVE-2026-102610 (this .md is for agents)

fast-agent's serve command exposes an MCP endpoint on all network interfaces at port 8000 with no authentication. When started with --shell, any client that can reach it can make the agent run operating-system commands as the server user; without --shell, the client can still use the operator's model and configured MCP tools.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed fast-agent version, for example with `pip show fast-agent-mcp` (package name is unknown from the sources; confirm it).
- Look for `fast-agent serve` processes or startup scripts that use `--shell`, and check whether port `8000` is reachable from other hosts.
- Confirm whether the server sits behind authentication or a firewall that blocks the `/mcp` endpoint.

## Fix

- fast-agent: move to `0.7.21` or later.

## Timeline

- 2026-11-06T21:45:07+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-102610

## Documents

- [advisory] Vendor advisory: github.com https://github.com/evalstate/fast-agent/security/advisories/GHSA-9vhv-g5hf-m7m7
- [fix] Patch: github.com https://github.com/evalstate/fast-agent/commit/ba99f89c3ec7f1ef1c8b1ebce381c12b60dfea29
- [fix] Release notes: github.com https://github.com/evalstate/fast-agent/releases/tag/v0.7.21

## From the sources

fast-agent is a framework for building, running, and evaluating AI agents with Model Context Protocol support. Prior to 0.7.21, fast-agent serve uses HTTP transport bound to 0.0.0.0 on port 8000 without authentication, allowing any network client that can reach the /mcp endpoint to invoke the exposed agent tool. When the server is started with --shell, the agent can call the local execute tool implemented by tools/local_shell_executor.py, so an unauthenticated remote client can cause operating-system commands to run as the server user; without --shell, the client can still consume the operator's model and configured MCP tools. The defaults are defined in cli/commands/serve.py and mcp/server/agent_server.py, and the non-interactive server permission prompt does not prevent the described access. This issue is fixed in version 0.7.21.

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