A note on the optimality of frequency analysis vs. ℓp-optimization
Marie-Sarah Lacharité, Paterson, Kenny · IACR Cryptology ePrint Archive · 2015
Naveed, Kamara, and Wright's recent paper "Inference Attacks on Property-Preserving Encrypted Databases" (ACM-CCS 2015) evaluated four attacks on encrypted databases, such as those based on the design of CryptDB (Popa et al., SOSP 2011). Two of these attacks---frequency analysis and l_p-optimization---apply to deterministically encrypted columns when there is a publicly-available auxiliary data set that is "well-correlated" with the ciphertext column. In their experiments, frequency analysis performed at least as well as l_p-optimization for p=1, 2, and 3. We use maximum likelihood estimation to confirm their intuition and show that frequency analysis is an optimal cryptanalytic technique in this scenario.A note on the optimality of frequency analysis vs. ℓpℓp-optimization