Card Security Code (CSC) is a security feature that protects against fraud. It ensures that credit card transactions can't be made without it being in the cardholder's possession.
Response Code
Message
M
The CSC matches the issuing bank’s records
N
The CSC does not match the issuing bank’s records
P
The CSC was not processed
S
The card should have a CSC, but merchant indicated it was not present
