Clever. I didn't get it at first. Never trust user input. Edit: See http://www.dnswatch.info/dns/dnslookup?la=en&host=jamiehanki... for the actual code.
> Never trust user input. Never trust any input. I think this is a case where people assume that is isn't pure user input because is would have already been parsed/checked/verified. "Oh, its in the DNS system so it must be safe" is worse then "well, it came from our database so it should be fine". Don't even trust something coming out of your own database. You never know what various input checking bugs might have ac…
This is only too true! At work we do CRUD projects, which means user input gets stored in the database. I almost always break other people's work by adding HTML tags to the inputs, navigating back to the page, and seeing markup that shouldn't be there. Even database output needs to be sanitized