A correlation duet: Correlation attacks on correlation generators

Pseudo-random correlation generators based on the Quasi-Abelian syndrome decoding problem were first attacked in an article published at Asiacrypt~2025, using compressed sensing. In this paper, we revisit the security of the problem using a more traditional cryptanalytic tool, namely correlation attacks.

As a result, we get a new cryptanalysis which outperforms the attack from Asiacrypt 2025 in several directions. It allows recovery of secret error polynomials with larger Hamming