Can You Hack It? Penetration Testing Gives Companies a Way to Find Their Vulnerabilities before Hackers Use Them to Break in and Cause Harm. (Computer Security)

Article excerpt

Although it may be true that crime doesn't pay, it pays to think like a criminal--if you want to avoid being victimized. That's the approach taken by cyberexperts hired to break into company networks to expose vulnerabilities. Known as ethical hackers, these computer savants perform penetration tests, which are controlled simulations of the actions and processes that might be taken by a malicious cyberattacker. The goal of a penetration test, as the name implies, is to penetrate the security of the target network and achieve certain objectives within an allocated time frame. These objectives may range from obtaining administrative access to mail servers to disabling a specific data center.

Rather than trying to find all the weaknesses in the target network, a cybercriminal looks for the path of least resistance, leveraging a few specific weaknesses that will provide unimpeded access to the target network. Emulating such a criminal, the penetration test team looks for the weakest links that will help it achieve its objectives. The penetration test is time based and evaluates whether a network can be cracked in a given amount of time, By contrast, a network vulnerability assessment looks at every component of the network to determine a wide variety of weaknesses. A penetration test is normally performed after a general network vulnerability assessment, providing both reinforcement and validation to the results of the broader test. However, sometimes a penetration test may precede a network vulnerability assessment to serve as convincing evidence to the need of performing a broader and more comprehensive test.

Types of tests. There are several types of penetration tests available in different combinations, depending on the objective of the company being tested. These are covert, overt, black-box, and crystal-box tests.

Covert vs. overt. In a covert test, most employees are unaware that the organization is being tested. In an overt test, system administrators know of the test and can watch the red team in action.

A covert test is more realistic than an overt one and can be used to measure the effectiveness and responsiveness of the defenses. However, such tests are generally longer in duration, as the test team must use slow and stealthy techniques to maintain a low profile and to avoid detection. Overt testing, although less realistic, provides valuable lessons for the organization's security members, as they are able to watch the attack in progress.

Black box vs. crystal box. In a "black box" test, the testing team has no insider knowledge of the target environment. As such, the team must spend a considerable amount of time discovering such information, if any can be found.

In a "crystal box" test, the team is given inside information about the company's network and may even work with insiders who have privileged information, such as the configuration of the network or the types of hardware and software in use.

The combination chosen depends on the objective of the test. For example, an international bank may decide to perform a covert, black-box penetration test to assess the security strength and responsiveness of its U.S. operations, while a domestic online book wholesaler may join a security firm in an overt, crystal-box penetration test against its own internal order procurement systems to determine potential threats from a disgruntled employee.

Most organizations favor the overt, black-box approach. The time and cost savings of an overt operation outweigh the effort of maintaining secrecy for a covert one, and a penetration test performed with no prior knowledge provides the realism that matters most; it helps the company assess the amount of sensitive information available to outsiders and how potential cyber-criminals would go about gathering and using such information.

Project BCS. To better illustrate the process, this article will walk the reader through a penetration test of the networks of a fictitious company called Bob's Computer Systems (BCS). …