Using asymmetric encryption to secure passwords

Question

Due to our customer\'s demands, user passwords must be kept in some \"readable\" form in order to allow accounts to be converted at a later date. Unfortunately, just saving hash

Answer 1

There is not enough information in the question to give any reasonable answer. Anyway since you disable padding there is a good chance that one of the attacks described in the paper "Why Textbook ElGamal and RSA Encryption are Insecure" by D. Boneh, A. Joux, and P. Nguyen is applicable.

That is just a wild guess of course. Your proposal could be susceptible to a number of other attacks.