After some recent breaks presented in the technical literature, it has become of paramount importance to gain a deeper understanding of the robustness and weaknesses of cryptographic hash functions. In particular, in the light of the recent attacks to the MD5 hash function, SHA-1 remains currently the only function that can be used in practice, since it is the only alternative to MD5 in many security standards. This work presents a study of vulnerabilities in the SHA family, namely the SHA-0 and SHA-1 hash functions, based on a high-performance computing application run on the MariCel cluster available at the Barcelona Supercomputing Center. The effectiveness of the different optimizations and search strategies that have been used is validated by a comprehensive set of quantitative evaluations, presented in the paper. Most importantly, at the conclusion of our study, we were able to identify an actual collision for a 71-round version of SHA-1, the first ever found so far.
A CellBE-based HPC application for the analysis of vulnerabilities in cryptographic hash functions / Cilardo, Alessandro; L., Esposito; A., Veniero; Mazzeo, Antonino; V., Beltran; E., Ayugadé. - ELETTRONICO. - (2010), pp. 450-457. (Intervento presentato al convegno International Conference on High Performance and Communications (HPCC) tenutosi a Melbourne nel 1-3 September 2010).
A CellBE-based HPC application for the analysis of vulnerabilities in cryptographic hash functions
CILARDO, Alessandro;MAZZEO, ANTONINO;
2010
Abstract
After some recent breaks presented in the technical literature, it has become of paramount importance to gain a deeper understanding of the robustness and weaknesses of cryptographic hash functions. In particular, in the light of the recent attacks to the MD5 hash function, SHA-1 remains currently the only function that can be used in practice, since it is the only alternative to MD5 in many security standards. This work presents a study of vulnerabilities in the SHA family, namely the SHA-0 and SHA-1 hash functions, based on a high-performance computing application run on the MariCel cluster available at the Barcelona Supercomputing Center. The effectiveness of the different optimizations and search strategies that have been used is validated by a comprehensive set of quantitative evaluations, presented in the paper. Most importantly, at the conclusion of our study, we were able to identify an actual collision for a 71-round version of SHA-1, the first ever found so far.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
