Video-Recording Power LEDs Can Lead to Cryptographic Key Theft by Hackers.

Researchers have discovered a new way to exploit side channels in smart cards and smartphones by using cameras in iPhones or commercial surveillance systems to video record power LEDs that show when the card reader or smartphone is turned on. The attacks enable the recovery of secret encryption keys stored in smart cards and smartphones, which underpin the security and confidentiality of a cryptographic algorithm. The video-based attacks reduce or completely eliminate the need for specialized and often expensive instruments attached or near the targeted device.