scepclient is a client implementation of Cisco System's Simple Certificate Enrollment Protocol (SCEP).
Note: This tool was written in 2005 and only got marginal updates since then. Hence, it implements an old version of the SCEP Internet Draft (version 10/11 of draft-nourse-scep, the most recent update was version 9 of draft-gutmann-scep in February 2018). So it might not be compatible with newer SCEP servers. It also uses default algorithms that are really not state-of-the-art anymore (MD5 to hash/sign and single DES to encrypt).