That was great advice for a while, but it is becoming less effective given the malware we are seeing these days. Patching once took care of a lot of the exploitable issues; however, this year we are seeing a record number of zero-day vulnerabilities in client-side software so that even keeping software patched isn't enough.
Antivirus has been fighting a losing battle for years because blacklisting is just not feasible in light of the amount of malware being released on a daily basis. Some interesting efforts are under way to make antivirus more effective; the one I saw most recently was the new MX-V behavioral detection within Sunbelt Software's VIPRE antivirus. Sunbelt's VP of threat research and technology gave a talk about MX-V last week at the University of Florida ITSA Day event. The video is posted here, and a recent blog entry about MX-V and Zbot is here.
Patching is ineffective when zero-days are involved. Antivirus can't keep up. So that leaves restricting users so they don't have administrative rights. Without admin rights, they can't run malware that takes control of the entire system. I know I've mentioned this before, but that's not the case anymore. Malware just wants a foothold in your system, and if it's only within one user profile, so be it. That's where application whitelisting comes into play.
If the user can't run it, then they can't get infected, right? Almost entirely true. There still has to be protections in place to prevent exploits from taking advantage of the latest vulnerability in Adobe Acrobat and injecting a malicious payload into memory. But coupled with memory protections, whitelisting is looking pretty good. Yesterday, I was brainstorming about ways to make it better with cloud-based functionality so there was reputation-based scoring that could be done for new executables in an environment. Turns out it has already being done by Bit9 as of April.
We all know a silver bullet doesn't exist when trying to protect our users, but some security solutions are certainly more effective than others and can sometimes replace multiple layers of protection that were once in place. It looks like application whitelisting could be one of those rare instances. Time to hit up those vendors that keep e-mailing me to see if they'll provide me with a few evaluation copies so I can see for myself.
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.