A group of security researchers has devised a new attack scheme to steal cryptographic keys from both Android and iOS devices. The attack works against the Elliptic Curve Digital Signature Algorithm (ECDSA) used in the majority of applications based on cryptographic algorithms, including Bitcoin wallets and Apple Pay. The researchers used a $2 magnetic probe placed near an iPhone 4 while the mobile devices were performing cryptographic operations to measure enough electromagnetic emanations and extract the secret cryptographic keys used by many different applications. The team also successfully tested the attack on a Sony-Ericsson Xperia X10 Phone running Android.”]
Source: http://securityaffairs.co/wordpress/45029/hacking/steals-secret-cryptographic-keys.html