Differential fault analysis on EMV application cryptogram

Abstract

The process of application cryptogram in EMV was researched and dummy bits in session key were found.Based on the session key’s dummy bits and compressive property of DES’s Sbox,much information of the application cryptogram master key was got by using safe-error attack.The differential fault attack model and steps to implement the attack were proposed,two key factors(the probability of generating wrong key and the probability of collision happening) affecting an attacking result were analyzed.The theoretical result and simulation of the attack were given.The experiment results show that the two keys could be distinguished in a real attacking when the dif-ference of two key’s collision probability was bigger than 0.003 5.The dummy bits in the key will increase the dif-ference and make distinguishing easier.Finally,several countermeasures against the attack were proposed.

Keywords

• emv
• application cryptogram
• collision attack
• safe-error