Basic user separation is not asking much though, or are we expected to believe that at ByteDance everyone has a wheel bit at a cluster worth many many millions? Let us see what turns up. Maybe they had a directory with Python pickles that were writeable by everyone? But even that is silly on a very basic level. As I said in another comment, I could be wrong and we have a mastermind cracker of an intern. But I somewhat doubt it.
I think we are converging at an opinion. Internal actors can be hard to detect, and honestly there is a reason at places like Google interns are treated with heightened security checks (my guess -- they learned to do so after some years).
Btw one of the rumors has that it is even difficult to hire engineers to do training/optimization infra at one of those ML shops -- all they want to hire are pure researcher types. We can imagine how hard it will be to ask for resources to tighten up security (without one of these incidents).
That level of security is true for most big tech companies :) You mistake thinking that large and well funded = secure. They clearly have an audit trail but no preventative controls, which is sadly the standard for move fast environments in big tech.
