Abstract: We studied three partially blind signature schemes,and found out the similarity in signature formulas of the three schemes.Then we compared and analized the three corresponding methods of“reduction attacks”,and the basic reason why these schemes are vulnerable to tampering common information attacks was pointed out.From the above analysis results,we deduced the conclusion that a class of partially blind signature schemes based on bilinear pairings are vulnerable to “reduction attacks”.Moreover,the deduction was verified．

Key words: Bilinear pairings,Partially blind signature,Tampering common information attacks