Group signatures are an important cryptographic primitive providing both
anonymity and accountability to signatures. Accountable ring signatures combine
features from both ring signatures and group signatures, and can be directly
transformed to group signatures. While there exists extensive work on
constructing group signatures from various post-quantum assumptions, there has
not been any using isogeny-based assumptions. In this work, we propose the
first construction of isogeny-based group signatures, which is a direct result
of our isogeny-based accountable ring signature. This is also the first
construction of accountable ring signatures based on post-quantum assumptions.
Our schemes are based on the decisional CSIDH assumption (D-CSIDH) and are
proven secure under the random oracle model (ROM)
