I am looking at the results of a mass vulnerability scan as I type this. Half of the bugs in one case are in fact (binary) parser errors for hand-written parsers. These really should not exist in any language - but in C it's particularly bad. Kaitai Struct or something similar would broadly have prevented these. Rust would help here, but less than a parser generator (because it could automate error checking insertion for things that aren't just out of bound access).

However, half of the vulnerabilities are logic errors in terms of what I would call RBAC enforcement, incorrect access permissions, and so on. Rust won't help at all with any of these.