What? It's about parsers in Go's standard library.

A "parser" is the piece of software that translates unstructured input (usually text) into structured output that better reflects the runtime of a programming language. A "security bug" in a parser is normally construed to be the existence of an input that causes the software to do something incorrect/undocumented/unexpected.

Nothing in the article discusses a parser or anything like a parser bug.

The article doesn't like that the semantics of the user-facing API wrapped around the parser is, I guess, "easy to make mistakes with". That's an article about API design, at most. But that's boring and specious and doesn't grab clicks, so they want you to think that Go's parsers are insecure instead.