Cryptanalysis of Round-Reduced HAS-160
نویسندگان
چکیده
HAS-160 is an iterated cryptographic hash function that is standardized by the Korean government and widely used in Korea. In this paper, we present a semi-free-start collision for 65 (out of 80) steps of HAS-160 with practical complexity. The basic attack strategy is to construct a long differential characteristic by connecting two short ones by a complex third characteristic. The short characteristics are constructed using techniques from coding theory. To connect them, we are using an automatic search algorithm for the connecting characteristic utilizing the nonlinearity of the step function.
منابع مشابه
Impossible Differential Cryptanalysis on Deoxys-BC-256
Deoxys is a final-round candidate of the CAESAR competition. Deoxys is built upon an internal tweakable block cipher Deoxys-BC, where in addition to the plaintext and key, it takes an extra non-secret input called a tweak. This paper presents the first impossible differential cryptanalysis of Deoxys-BC-256 which is used in Deoxys as an internal tweakable block cipher. First, we find a 4.5-round...
متن کاملImpossible Differential Cryptanalysis of Reduced-Round Midori64 Block Cipher (Extended Version)
Impossible differential attack is a well-known mean to examine robustness of block ciphers. Using impossible differ- ential cryptanalysis, we analyze security of a family of lightweight block ciphers, named Midori, that are designed considering low energy consumption. Midori state size can be either 64 bits for Midori64 or 128 bits for Midori128; however, both vers...
متن کاملA new method for accelerating impossible differential cryptanalysis and its application on LBlock
Impossible differential cryptanalysis, the extension of differential cryptanalysis, is one of the most efficient attacks against block ciphers. This cryptanalysis method has been applied to most of the block ciphers and has shown significant results. Using structures, key schedule considerations, early abort, and pre-computation are some common methods to reduce complexities of this attack. In ...
متن کاملCryptanalysis and design of symmetric primitives
This thesis focuses on the cryptanalysis and the design of block ciphers and hash functions. The thesis starts with an overview of methods for cryptanalysis of block ciphers which are based on differential cryptanalysis. We explain these concepts and also several combinations of these attacks. We propose new attacks on reduced versions of ARIA and AES. Furthermore, we analyze the strength of th...
متن کاملOn the Collision Resistance of RIPEMD-160
In this article, the RIPEMD-160 hash function is studied in detail. To analyze the hash function, we have extended existing approaches and used recent results in cryptanalysis. While RIPEMD and RIPEMD-128 reduced to 3 rounds are vulnerable to the attack, it is not feasible for RIPEMD-160. Furthermore, we present an analytical attack on a round-reduced variant of the RIPEMD-160 hash function. To...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2011