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Hier finden Sie wissenschaftliche Publikationen aus den FraunhoferInstituten. Clustering algorithms for nonprofiled singleexecution attacks on exponentiations
 Francillon, A.: Smart card research and advanced applications. 12th international conference, CARDIS 2013 : Berlin, Germany, November 2729, 2013; Revised selected papers Cham: Springer International Publishing, 2014 (Lecture Notes in Computer Science 8419) ISBN: 9783319083018 (Print) ISBN: 9783319083025 (Online) S.7993 
 International Conference on Smart Card Research and Applications (CARDIS) <12, 2013, Berlin> 

 Englisch 
 Konferenzbeitrag 
 Fraunhofer AISEC () 
Abstract
Most implementations of public key cryptography employ exponentiation algorithms. Sidechannel attacks on secret exponents are typically bound to the leakage of single executions due to cryptographic protocols or sidechannel countermeasures such as blinding. We propose for the first time, to use a wellestablished class of algorithms, i.e. unsupervised cluster classification algorithms such as the kmeans algorithm to attack cryptographic exponentiations and recover secret exponents without any prior profiling, manual tuning or leakage models. Not requiring profiling is of significant advantage to attackers, as are wellestablished algorithms. The proposed nonprofiled singleexecution attack is able to exploit any available singleexecution leakage and provides a straightforward option to combine simultaneous measurements to increase the available leakage. We present empirical results from attacking an FPGAbased elliptic curve scalar multiplication using the k mean s clustering algorithm and successfully exploit locationbased leakage from highresolution electromagnetic field measurements to achieve a low remaining bruteforce complexity of the secret exponent. A simulated multichannel measurement even enables an errorfree recovery of the exponent.