@article{Connolly_Farshim_Fuchsbauer_2019, title={Security of Symmetric Primitives against Key-Correlated Attacks}, volume={2019}, url={https://tosc.iacr.org/index.php/ToSC/article/view/8363}, DOI={10.13154/tosc.v2019.i3.193-230}, abstractNote={<p>We study the security of symmetric primitives against <em>key-correlated attacks </em>(KCA), whereby an adversary can arbitrarily correlate keys, messages, and ciphertexts. Security against KCA is required whenever a primitive should securely encrypt key-dependent data, even when it is used under related keys. KCA is a strengthening of the previously considered notions of related-key attack (RKA) and key-dependent message (KDM) security. This strengthening is strict, as we show that 2-round Even–Mansour fails to be KCA secure even though it is <em>both </em>RKA and KDM secure. We provide feasibility results in the ideal-cipher model for KCAs and show that 3-round Even–Mansour is KCA secure under key offsets in the random-permutation model. We also give a natural transformation that converts any authenticated encryption scheme to a KCA-secure one in the random-oracle model. Conceptually, our results allow for a unified treatment of RKA and KDM security in idealized models of computation.</p>}, number={3}, journal={IACR Transactions on Symmetric Cryptology}, author={Connolly, Aisling and Farshim, Pooya and Fuchsbauer, Georg}, year={2019}, month={Sep.}, pages={193–230} }