Incompressible Encryption Beyond CPA/CCA Security
Venkata Koppula, Abhinav Kumar, Mahesh Rajasree, Harihar Swaminathan · IACR Communications in Cryptology · 2025
An incompressible encryption scheme offers protection against adversaries who possess the entire secret key but can store only a portion of the ciphertext. In recent years, there has been growing interest in developing such primitives in both public-key and secret-key settings, as well as in the multi-user scenario. In this work, we extend the concept of incompressible encryption to incorporate anonymity and key-dependent message security. We introduce the following schemes: 1. The first key-dependent message incompressible SKE scheme secure against unbounded adversaries. 2.The first anonymous incompressible SKE scheme secure against unbounded encryption queries. Furthermore, we present the public key versions of these schemes.