Local File Access MCP Server

Path Traversal Vulnerability: CRITICALThe server does not properly validate file paths, allowing access to files outside intended directories

# No path validation or normalization
file_path = tool_input['path']
with open(file_path, 'r') as f:
    content = f.read()
return content

import os
from pathlib import Path

# Define allowed base directory
BASE_DIR = "/app/allowed_files"
file_path = tool_input['path']

# Normalize and validate path is within allowed directory
abs_path = os.path.abspath(os.path.join(BASE_DIR, file_path))
if not abs_path.startswith(BASE_DIR):
    raise SecurityError("Access denied: Attempted path traversal")

with open(abs_path, 'r') as f:
    content = f.read()
return content

File System Access Control: CRITICALNo restrictions on which system files can be accessed or modified

Input Validation: HIGH RISKInsufficient validation of input parameters

Excessive Tool Permissions: CRITICALTools have unrestricted access to the file system without user-specific sandboxing

# All file operations run with server process permissions
# No user-specific sandboxed environments
# No separation between users accessing the same server

# Create user-specific sandboxed directories
# Implement proper permission model with read/write restrictions
# Use containerization to isolate each user's file operations

Undefined Tool Boundaries: HIGH RISKNo clear definition of what files the tools should be allowed to access

Tool Documentation: RECOMMENDATIONImprove tool documentation to clearly state security limitations and intended usage

Data Encryption: SECURE

Input Sanitization: RECOMMENDATIONImplement consistent sanitization of file content before writing to disk

Logging & Monitoring: RECOMMENDATIONAdd comprehensive logging for all file operations to detect potential abuse

Default Permissions: CRITICALServer runs with excessive system permissions by default

Configuration File: RECOMMENDATIONImplement a configuration file to define allowed directories and operations