Does 3ds Max offer a native sandbox for executing untrusted MAXScripts?

Answer the exact question first

3ds Max does not provide a native sandbox or restricted‑mode for executing MAXScript or Python. All scripts run with the full privileges of the Windows account that launched Max, meaning they can read/write any file the user can access, launch external processes, and call .NET APIs without internal restriction.

Why this matters

• Scene files can contain scripted controllers or callbacks that execute automatically when the file is opened.
• Without a sandbox, opening an asset from an untrusted source can run arbitrary code without user confirmation.
• There is no undocumented setting that limits filesystem or network access for scripts.

How to verify script privileges

1. Create a new .max file.
2. Insert the following MAXScript snippet and save the file:

   -- Test script – write to a protected folder
   local filePath = "C:\\Windows\\Temp\\maxscript_test.txt"
   try(
       local f = createFile filePath
       format "Script ran successfully. File created at: %\n" filePath
       close f
       print "File written"
   catch(error)
       print ("Error: " + error)
   

3. Run the script in the 3ds Max listener or via runScript.
4. If the file appears in C:\Windows\Temp, the script had full filesystem access.

Mitigation without an internal sandbox

• Run 3ds Max under a dedicated, low‑privilege Windows account that only has the necessary read/write rights for your production directories.
• Use Windows Defender Application Control (WDAC) or AppLocker to block execution of scripts or external binaries that are not signed or whitelisted.
• Configure group policy to restrict dosCommand usage or limit the ability to launch arbitrary processes.
• If you rely on Python scripts, ensure the python executable is the one bundled with Max and that no untrusted Python modules can be imported.

What you might still need to know

Do you currently use any third‑party plug‑in that adds sandboxing or script‑execution limits? If so, the recommendation above may change, because such plug‑ins can provide an additional layer of protection that is not part of the core application.