I worked on V8 for almost 7 years. It being written in C++ is a cause of a large number of issues. And even larger number of issues is caused by its absolutely massive complexity and the low-level nature of what it does, particularly the object model and the JIT compiler's complex optimizations. Low-level is really dangerous and error prone.
I think every VM should be rewritten in a memory-safe, GC'd language. While there are bugs at the meta-level (i.e. the compiler IR and object representation), making the runtime code itself memory-safe should be table stakes for even talking about a trustworthy implementation.
I think every VM should be rewritten in a memory-safe, GC'd language. While there are bugs at the meta-level (i.e. the compiler IR and object representation), making the runtime code itself memory-safe should be table stakes for even talking about a trustworthy implementation.