When I’m browsing the web, occasionally I’ll happen upon an image where a portion is blurred or pixelated to block sensitive information such as a number. This irks me to no end, because as this article by Dheera Venkatraman demonstrates, blurring can be cracked in the same way one might crack a weak password, with a dictionary attack.
Why would someone blur an alphanumeric string when they could just as easily erase or cover it altogether? This is a classic example of having good intentions but making poor choices. I can understand a blurred face, but something as easily cracked as short numbers… you can do better Internet. Dheera sums it up much more eloquently than I can:
“Remember, you want to leave your visitors with NO information, not blurred information.”