Relying on php to open an url? Or do you mean filename="/" ? What did your attempt end up being? (Apparently they've taken down the ctf-servers, so playtime is over).
Yes.
You can do $x = file_get_contents("http://news.ycombinator.com) and it will work (well, in that case it wouldn't as the machine had locked down network access, but you get the idea).
Yes, I am aware php allows one to open urls via the file*-procedures (unless it has been disabled on the server -- which is generally a good idea for production deployment). I meant -- what did you end up using for the challenge (url/$filename and $attempt)?
