Today ERP system and software has three layer of interfaces -
network layer
presentation layer
application layer
Security problems exist in every face of the ERP software like - entry in business processes, internal interfaces and internal database. The security problem will persist in those scenarios where different business components will interact with each other and the client and customers will interact with the whole system. In those scenarios, a small error can be lethally fatal.
Security approaches to the organization -
New security policies should be easily defined and maintained by the organization time to time.
Accessing/denying permission to users carefully by the administrators
To perform the user authentication properly for the new and old regular users
Task performing privileges should be done properly by the certain users or roles
The user is granted access as per according to the authorization rules
Timely verification is necessary for to access the relevant sources
Properly logging and tracing of the relevant events  
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