Improved Truncated Differential Attacks on SAFER
نویسندگان
چکیده
Knudsen and Berson have applied truncated differential attack on 5 round SAFER K-64 successfully. However, their attack is not efficient when applied on 5 round SAFER SK-64 (with the modified key schedule) and can not be applied on 6 round SAFER. In this paper, we improve the truncated differential attack on SAFER by using better truncated differential and additional filtering method. Our attack on 5 round SAFER (both SAFER K-64 and SAFER SK-64) can find the secret key much faster than by exhaustive search. Also, the number of chosen plaintexts required are less than those needed in Knudsen and Bersons attack. Our attack on 6 round SAFER (both SAFER K-64 and SAFER SK-64) can find the secret key faster than by exhaustive search.
منابع مشابه
Protecting Against Multidimensional Linear and Truncated Differential Cryptanalysis by Decorrelation
The decorrelation theory provides a different point of view on the security of block cipher primitives. Results on some statistical attacks obtained in this context can support or provide new insight on the security of symmetric cryptographic primitives. In this paper, we study, for the first time, the multidimensional linear attacks as well as the truncated differential attacks in this context...
متن کاملImpossible Differential Attacks on Reduced-Round SAFER Ciphers∗ NES/DOC/KUL/WP5/30/1
This report describes impossible differential (ID) attacks on 3.75round SAFER SK-64, using 2 chosen texts, 2 memory, and 2 time. Moreover, an ID attack on both 2.75-round SAFER+ and on 2.75-round SAFER++ uses 2 data, 2 memory, and 2 time. We used the miss-in-the-middle technique developed by Biham et al. These attacks do not endanger the security of SAFER ciphers, and indicate that ID attacks w...
متن کاملNew Impossible Differential Attack on SAFER + and SAFER + +
SAFER+ was a candidate block cipher for AES with 128-bit block size and a variable key sizes of 128, 192 or 256 bits. Bluetooth uses customized versions of SAFER+ for security. The numbers of rounds for SAFER+ with key sizes of 128, 192 and 256 are 8, 12 and 16, respectively. SAFER++, a variant of SAFER+, was among the cryptographic primitives selected for the second phase of the NESSIE project...
متن کاملImproved Differential Attacks for ECHO and Grøstl
We present improved cryptanalysis of two second-round SHA-3 candidates: the AESbased hash functions ECHO and Grøstl. We explain methods for building better differential trails for ECHO by increasing the granularity of the truncated differential paths previously considered. In the case of Grøstl, we describe a new technique, the internal differential attack, which shows that when using parallel ...
متن کاملImproved Meet-in-the-Middle Distinguisher on Feistel Schemes
Improved meet-in-the-middle cryptanalysis with efficient tabulation technique has been shown to be a very powerful form of cryptanalysis against SPN block ciphers. However, few literatures show the effectiveness of this cryptanalysis against Balanced-Feistel-Networks (BFN) and Generalized-Feistel-Networks (GFN) ciphers due to the stagger of affected trail and special truncated differential trai...
متن کامل