Posterior Security: Anonymity and Message Hiding of Standard Signatures
Tsz Hon Yuen, Ying-Teng Chen, Shimin Pan, Jiangshan Yu, Joseph K. Liu · 2025
We introduce posterior security of digital signatures, the additional security features after the original signature is generated. It is motivated by the scenario that some people store their secret keys in secure hardware and can only obtain a standard signature through a standardized interface. In this paper, we consider two different posterior security features: anonymity and message hiding.