Plimus Inc. is a company that handles online payments for websites. The websites don’t have to deal with all kinds of credit card companies and banks. Just create a account at Plimus and let them handle all your payments. This means Plimus has access to sensitive customer information and they should take extremely good care to protect this information. However, I will try to explain how a few mistakes from Plimus may harm the security of your webshop and the security of your customers.