21 April 2010

When To Choose: Preventive VS Reactive #Security

Posted by John Sawyer, Mar 31, 2010 03:32 PM 

Information security is an area of IT that can have an extremely varied budget based on the parent organizations' belief of whether or not they'll be hacked. It's a mentality that seems silly if you've been in the infosec biz for a while because you most likely have realized by now that everyone gets hacked or has a data breach at some point.

We’re faced with a tough question. How do we get management to buy into that mentality? Better yet, do we want them to? It's not easy telling your boss that a data breach is inevitable. That's not what bosses like to hear, but either way, someone is going to lose a cell phone or USB flash drive, have a laptop stolen, or an attacker is going to break in through a SQL injection vulnerability in your Web app or via information socially engineered over the phone.

You know what your boss is going to say next…"We need to prevent those things!" And, that's where we stuck with trying to prevent every possible breach scenario that we can think of, even those we can't think of via methods that haven't been discovered. One of the things you have to decide is how to balance preventive security with that of reactive security. In other words, do you spend money on laptop encryption and patch management or intrusion detection and centralized log monitoring?

I keep thinking back to Dave Shackleford's blog entry, "
5 Reasons Your Security Program is a Failure." There are several great points there, but the one that I keep thinking about is #2, Lack of monitoring capabilities. Where does monitoring fall in terms of preventive and reactive security?

In the incident response process, monitoring fits nicely in the identification stage. Alerts coming from an intrusion detection system can identify a compromised host because an attack was seen followed by a command shell.
But, can't monitoring be preventive, also? For example, monitoring changes on workstations could turn up an employee plugging in an external USB drive and trying to access documents that he or she isn't authorized to access. Security could respond immediately and prevent a potential data breach before the employee has a chance to copy files and leave. Hmm…doesn’t that still seem a little reactive?

So, where does monitoring fit? We all know we need to have log analysis and intrusion detection systems in place, but where do we draw the line? Should we ever place the need to have monitoring technologies over patch management and application whitelisting that could prevent infections and compromises that we’d be using the monitoring systems to detect?
My choice would be the preventive technologies first, then the monitoring because I know I can implement cheap, open source monitoring tools in the interim while waiting for additional budget for more costly, enterprise monitoring solutions. The problem is when you don’t have the budget for both. What then? I’d love to get some feedback from those of you facing shrinking budgets and what choices and sacrifices you’ve had to make. 

John H. Sawyer is a senior security engineer on the IT Security Team at the University of Florida. The views and opinions expressed in this blog are his own and do not represent the views and opinions of the UF IT Security Team or the University of Florida. When John's not fighting flaming, malware-infested machines or performing autopsies on blitzed boxes, he can usually be found hanging with his family, bouncing a baby on one knee and balancing a laptop on the other. Special to Dark Reading.