Call this a sneak into the future, but it's now possible to read thy brain, or rather hack it. Indeed. Researchers at Usenix Security conference have used a commercially available brain-computer interface (BCI) to demonstrate the very same. The brain-computer interface's hardware includes a headset (an electroencephalograph or EEG) with sensors which shall ease up on your scalp, while the software deals with your brain activity trying to understand your activity. The BCIs are generally used in medical settings along with expensive equipments, but past few years have seen the emergence of similar cheaper products that are commercially available, like Emotiv (one that's shown in the picture).
The BCI has an interface (API) that allows developers to employ BCI's output in their respective programs. Here, the security researchers (from Oxford, California and Geneva University) made up a custom program that was designed solely to trace out sensitive data- like your credit card number, your DOB, etc. Then this programme was tested on 28 participants (who were unaware that their brain's being hacked). Now the information was to be extracted using the P300 response, which is a brainwave pattern that appears when you recognize a meaningful object/activity. Analyzing this patterns/pictures, the data is dug out with great accuracy.
Well, in the real world, the researchers predict of a game where the hackers could dig out some of your sensitive information while promising you a false sense of security. And as the BCIs continue to get cheaper, the chances of this happening is pretty high.