Modern C++ does not mandate that every value be a valid instance of its type wherever it is theoretically accessible, so I'm not sure why you're saying modern C++ fixes this. Actually, the fact that Rust does is something people somewhat regularly complain about. It is a heavy-handed performance / code complexity vs. safety tradeoff that certainly fixes this bug, which I think is a pretty reasonable thing to point out.
If you follow C++14 core guidelines, the defect described would not have occurred. The bug at its core is usage of unsanitized input data. You don't need to "mandate that every value be a valid instance of its type wherever it is theoretically accessible", however that may differ from simple sane C++14 paradigms.
OPINION ALERT: Honestly guys get over rust, it does not offer a single advantage in real-life programming scenarios.
The C++ compiler can't enforce many of these rules (and many of the ones it does claim to enforce, it only does heuristically), and the document itself is not shy about admitting that. It also makes quite clear that it expects not just mechanical checking, but things like peer review, to take these guidelines into account--meaning yes, you are expected to know a large portion of the document. Also, a lot of the listed enforcement mechanisms are literally just flagging suspicious code--you would have to disable a tremendous number of such flags to execute many perfectly reasonable programs. Stop misleading people about the contents of this document actually being enforced by the compiler, please.
