The problem is that you're encouraging people to keep stuff like this to themselves until they can use it to perform an exploit that they'd get paid for, which is the opposite of what Microsoft wants - they'd much rather you report it now so that if an exploit does get found that requires root they would potentially be protected.
The simple question for Microsoft to answer is - does it matter to them if attackers have root access on the container? If the answer is yes then the bug bounty for root access should at least pay something to encourage reporting. If the answer is no then this shouldn't have been marked as a vulnerability because root access is not considered a security issue.
But a $5 wrench isn't a critical security vulnerability just because someone somewhere might one day find the right person to apply it to to extract important credentials.
Not really the right metaphor. A $5 wrench isn't a "vulnerability" because it's $5! Tools that are accessible to everyone are part of the threat model, not something you can eliminate or avoid. This trick is novel and new.
Like, consider your personal cult was built around an "unopenable" bolt-tighted box. Then someone invents the wrench in an attempt to open it. That would be a clear "security vulnerability", right?
Not a serious one if all the wrench actually gets you is access to the room that contains the box that no known tool can open, which is a closer analogy to what happened.
Again, though, you're taking "all that gets you" as a prior when (abandoning the metaphor) container and VM escapes are routine vulnerabilities. They just weren't the subject of this particular team who wanted to hack on AI. You don't do security analysis by presuming the absence of vulnerabilities!
Modern security is defense in depth. The AI pre-prompting setup was the first layer, and it was escaped. The UID separation inside the container was another, and it was broken. The container would have been next. And hopefully there are network firewalls and egress rules on top of that, etc... And all of those can and have failed in the past.
And an exploit that breaks out of the sandbox is not really anything if it needs root to work... so if a hacker had those two MS wouldn't care about them selling those bugs because both of them are not serious. See, perfect security and it didn't cost them anything.
Microsoft have a bug bounty program which is credible and well run.
Suing people who responsibly disclose security issues to you is a disastrous thing to do. Word spreads instantly and now you won't get any responsibly disclosed bug reports in the future.
Are there any known unfixed container breakouts at the moment in the kind of systems Microsoft are likely to be using here?