Quick Response (QR) codes can be really nice. You see an ad in a magazine or a poster on a wall and want more info? Just point your smart phone at the pattern and scan it with the appropriate app and, voila, all the detail you could care to know pops up in your hand.
At least, that’s how it’s supposed to work when everybody plays nice, and most people do. Of course, if you’ve been reading this blog at all, you know that not everyone does and that for every new turn of the technological crank brings not only great opportunity to do some really cool things but also an equal opportunity that bad actors can exploit do to some really not so cool things. QR codes are no different.
For example, here’s a QR code that contains a link to this blog. It would be easy to add more info such as a phone number, email address, etc. but let’s keep it simple.
A QR reader app on your phone should be able to verify this for you. (Note: you may have to print it off and then try scanning the printed version if your phone’s camera has trouble reading it.)
But what if I was a bad guy and instead of pointing you to a benign site, I sent you to a malicious site which automatically downloaded malware to your phone that then sent me a copy of your confidential emails, stored passwords/acct numbers, contacts, text messages, etc. and started sending SMSs to premium services without your knowledge and racked huge charges for you? Not so good, right?
How can you tell just by looking at a QR code whether it is good or bad? The answer is, you can’t, and that’s the problem. Bad guys know this and some have taken to printing up their own QR codes and sticking them over the top of legitimate ones so as to snare unsuspecting victims.
The better QR reader apps will show you the link they have scanned first so that you can then choose whether to send your browser there or not. Unfortunately, if the bad guy has used a URL shortener such as bitly, TinyURL or others, the actual web site you will be taken to may still be obscured from view.
So, be careful. The best advice is to “trust, but verify.”