I admire your optimism, but the notion that missing access checks are somehow less dangerous in a memory safe language is nonsense on its face.
Yes, this particular one enabled a defeat of ASLR, but so what?
Missing access checks enable privilege escalation no matter what the language.
Your claim that "has well-definable consequences" is equally true in C++ as anywhere else.
Whether you miss your access check in rust, or C++, or python, or whatever, the definable consequences are "privilege escalation".
Let's not pretend memory safe languages solve logic problems.
They help with memory safety - that's awesome but not a complete solution.
If we want better verification of access contracts, we'd need a language with contracts or some other verifiable mechanism.
Those exist, and i'd support their use in this sort of case.