New Multi-bit Differentials to Improve Attacks Against ChaCha. - Murilo Coutinho; T. C. Souza Neto (IACR Cryptol. ePrint Arch., 2020)

Improved Linear Approximations to ARX Ciphers and Attacks Against ChaCha. - Murilo Coutinho; T. C. Souza Neto (IACR Cryptol. ePrint Arch., 2021)