Ghostscript and xPDF for X Windows always had this functionality. Back from the days when adobe.com didn't need a firewall and everyone had keys to everyone else's locks and doors were made of paper, isn't it nice to see leftovers from this world?

There's a readme file in the xPDF distribution which discusses why ignoring the protection would be a bad thing - and so far, nobody has busted this package up so it does.