Paper 2019/807

Provably Secure PKI Schemes

Hemi Leibowitz and Amir Herzberg and Ewa Syta

Abstract

PKI schemes have significantly evolved since X.509, with more complex goals, e.g., transparency, to ensure security against corrupt issuers. However, due to the significant challenges involved and lack of suitable framework, the security properties of PKI schemes have not been rigorously defined or established. This is concerning as PKIs are the basis for security of many critical systems, and security concerns exist, even for well known and deployed PKI schemes, e.g., Certificate Transparency (CT). We present precise definitions allowing provably secure PKI schemes, with properties such as accountability, transparency and non-equivocation. We demonstrate usage of the PKI framework against X.509 version 2.