A Provable-Security Analysis of Intel’s Secure Key RNG

  • Thomas ShrimptonEmail author
  • R. Seth Terashima
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9056)


We provide the first provable-security analysis of the Intel Secure Key hardware RNG (ISK-RNG), versions of which have appeared in Intel processors since late 2011. To model the ISK-RNG, we generalize the PRNG-with-inputs primitive, introduced by Dodis et al. at CCS’13 for their /dev/[u]random analysis. The concrete security bounds we uncover tell a mixed story. We find that ISK-RNG lacks backward-security altogether, and that the forward-security bound for the “truly random” bits fetched by the \(\mathtt {RDSEED}\) instruction is potentially worrisome. On the other hand, we are able to prove stronger forward-security bounds for the pseudorandom bits fetched by the \(\mathtt {RDRAND}\) instruction. En route to these results, our main technical efforts focus on the way in which ISK-RNG employs CBCMAC as an entropy extractor.


Random number generator Entropy extraction Provable security 


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Copyright information

© International Association for Cryptologic Research 2015

Authors and Affiliations

  1. 1.Department of Computer SciencePortland State UniversityPortlandUSA

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