Solve the problem with website security

Employer
[no-member:pro]Sergey[/no-member:pro]Sergey
Project parameters
Type of cooperationOn a permanent basis
SectionWeb development
Prepaymentprepayment is possible
Payment methodsElectronic money
Acceptance of requestsclosed
Project description
Online store (post box, SAP) on a self-written CMS is connected to mass payments (API) to PAYEER. The villain stole all the money from the account in Payer, and as a Bux Administrator.