Page 589 - (ISC)² CISSP Certified Information Systems Security Professional Official Study Guide

Database Systems Security

Database security is an important part of any organization that uses
large sets of data as an essential asset. Without database security
efforts, business tasks can be interrupted and confidential information

disclosed. For the CISSP exam, it is important that you are aware of
several topics in relation to database security. These include
aggregation, inference, data mining, data warehousing, and data
analytics.

Aggregation

SQL provides a number of functions that combine records from one or
more tables to produce potentially useful information. This process is
called aggregation. Aggregation is not without its security
vulnerabilities. Aggregation attacks are used to collect numerous low-
level security items or low-value items and combine them to create

something of a higher security level or value.

These functions, although extremely useful, also pose a risk to the
security of information in a database. For example, suppose a low-
level military records clerk is responsible for updating records of
personnel and equipment as they are transferred from base to base. As
part of his duties, this clerk may be granted the database permissions
necessary to query and update personnel tables.

The military might not consider an individual transfer request (in

other words, Sergeant Jones is being moved from Base X to Base Y) to
be classified information. The records clerk has access to that
information because he needs it to process Sergeant Jones’s transfer.
However, with access to aggregate functions, the records clerk might
be able to count the number of troops assigned to each military base
around the world. These force levels are often closely guarded military

secrets, but the low-ranking records clerk could deduce them by using
aggregate functions across a large number of unclassified records.

For this reason, it’s especially important for database security
administrators to strictly control access to aggregate functions and