Structural Cryptanalysis of a Class-2 Nilpotent Lie Algebra Signature Candidate: Linearization and Equivalent-Secret Forgery
This study presents a structural cryptanalysis of a Fiat–Shamir-type digital-signature candidate based on class-2 nilpotent Lie algebras over finite fields. We show that the public transformation is linear in the signing secret and that public-key inversion reduces to a consistent linear system over the underlying fini...