Applied Oracle Security: Developing Secure Database and Middleware Environments- P36:Computer security is a field of study that continues to undergo significant changes at an extremely fast pace. As a result of research combined with increases in computing capacity, computer security has reached what many consider to be “early adulthood.” From advances in encryption and encryption devices to identity management and enterprise auditing, the computer security field is as vast and complex as it is sophisticated and powerful | 324 Part II Oracle Database Vault This audit trail records reveal a pattern that involves three SELECT statements followed by an INSERT statement and then an UPDATE statement on tables related to product costs. We can assert that this sequence of statements constitute the normal context of the transaction. You can then develop DBV factors that query the audit trail for the records to validate the correct sequence of statements. It is possible that data other than the audit trail records exists which you can use to perform this validation. You can use these factors in your DBV rules to prevent direct INSERT or UPDATE statements on the cost-related table unless the proper transactional sequence can be verified. This approach is similar to the types of controls you might find in an intrusion detection system IDS that performs pattern matching and anomaly detection. Factors Based on Data or Events Stored Externally The use of identity management information when coupled with Oracle EUS is one form of a DBV factor that is based on information stored externally. Many Oracle database environments reach out to other systems on the same network to retrieve information for one purpose or another. There is no reason you cannot use these external systems for event information that would be useful to your DBV security policy. This information could be as simple as supplemental data about the current user that is not stored in an identity management infrastructure but is stored in a human resources system. An advanced usage could even query a physical access system used by the company to determine whether the user swiped his or her access badge to get into the building at some point in the business day. We can use several queries to determine whether a database relies on external system for information. First we can check for the dependency on the following types of PL SQL routines by custom database application code Oracle file-based APIs UTL_FILE Oracle network-based APIs .
