In addition to rewriting the tools in Rust, a safer language, some little-used features of sudo were not implemented in order to reduce vulnerability surface area. This turned out to be meaningful in July of 2025 when two vulnerabilities (..) were discovered in sudo features not implemented in sudo-rs. In response to one of those, sudo has deprecated and will remove the feature hosting the vulnerability.
– Josh Aas on the prossimo blog
I like the quote because it shows that a) Rust doesn’t solve every problem (though it does solve a few), and b) it can be a very good idea not to implement all features.