Generic CPA Decryption Attack on Ascon-128 in Nonce-Misuse Setting by Exploiting XOR Patterns

Ascon cipher has been chosen by NIST for standardization of lightweight cryptography. It has many variants that provide authenticated encryption with associated data (AEAD) and hashing functionalities. Since the beginning of the NIST lightweight cryptography competition, Ascon has been analyzed from various prospectives, including linear analysis, differential analysis, and chosen-plaintext attacks (CPA). This paper is introducing a new approach for a chosen-plaintext attack on Ascon-128 in nonce-misuse setting. It explains how patterns can be extracted from the bitwise XOR operation and exploited to perform the attack. The results show that this attack requires 160 queries to the encryption oracle for each ciphertext block decryption. This is more than the number of required queries in one of the previous works that proposed a CPA attack that requires only one query for each ciphertext block decryption. However, this paper introduces a new approach to perform this kind of attack.