> What you’re NOT protecting against:
> a malicious AI trying to escape the VM (VM escape vulnerabilities exist, but they’re rare and require deliberate exploitation)
No VM escape vulns necessary. A malicious AI could just add arbitrary code to your Vagrantfile and get host access the first time you run a vagrant command.
If you're only worried about mistakes, Claude could decide to fix/improve something by adding a commit hook. If that contains a mistake, the mistake gets executed on your host the first time you git commit/push.
(Yes, it's unpleasantly difficult to truly isolate dev environments without inconveniencing yourself.)
Doesn't this assume you bi-directionally share directories between the host or the VM? Or how would the AI inside the VM be able to write to your .git repository or Vagrantfile? That's not the default setup with VMs (AFAIK, you need to explicitly use "shared directories" or similar), nor should you do that if you're trying to use VM for containment of something.
I basically do something like "take snapshot -> run tiny vm -> let agent do what it does -> take snapshot -> look at diff" for each change, restarting if it doesn't give me what I wanted, or I misdirected it somehow. But there is no automatic sync of files, that'd defeat the entire point of putting it into a VM in the first place, wouldn't it?
Another way is malicious code gets added to the repo, if you ever run the repo code outside the VM you get infected.