I've always viewed 4chan as hardcore chaotic neutral. They're quite happy to find novel solutions to mathematical problems, DDoS people they don't like, openly work with leaked source code, create a new chat system (tox), troll celebrities... they don't care about good/bad, they care about whatever strikes them as interesting or fun. Which is... a very mixed bag:)
Through it's very unlikely.
But you always have that risk when downloading anything (from anywhere).
4chan is a very special place, it has many "good" people but it also has "bad" people.
(Note that both "good" and "bad" are very opinionated, which is why they are quoted).