Good link. After reading this it's not a surprise that this code has security vulnerabilities. But of course from knowing that there must be more to actually finding it, it's still a big leap.
4 years after the article, does any relevant distro have that implementation enabled?
https://lwn.net/Articles/871866/ This is also nothing to do with Samba which is a well trodden path.
So why not attack a codebase that is rather more heavily used and older? Why not go for vi?