Remark on self-certified group-orientedcryptosystem without combiner
Willy Susilo, Reihaneh Safavi–Naini · Electronics Letters · 1999
In a (t, n) group-oriented cryptosystem, the collaboration of at least t participants is required to perform the designated cryptographic operation. It is shown that a recently proposed group-oriented encryption scheme by Saeednia and Ghodosi is insecure and allows two participants to collude and decrypt an encrypted message.