The blacklist approach is inherently flawed. By it's nature, Python has a surprisingly large surface area, and you will forever be at the mercy of having to vet every possible built-in command, along with each and every side effect of the built-ins. Not to mention, I assume the real script you're using will bring in some library, itself a protentional security concern.

For instance:

__builtins__.__dict__'Exec'.lower())")

This bypasses your checks, and lets the user call exec and import. This is not the only way to bypass your checks. There are others.

There isn't really a way to vet code to verify its safe automatically. I'd be hard pressed to imagine a scenario like this where I let users run code at all in an elevated environment.

you’ll still creds to get into the infrastructure… what about Powershell? then AD only requires read access to get a huge amount of information about your company’s systems and users.

Not more of less an issues than anything else … imho