Most of the organizations that I've worked with tend to take more of a hybrid approach. Automatic patching processes occur for the majority of their systems, while more critical systems go through a vetting process with identical test systems to prevent possible conflicts between the patch and the production environment. Though the patch for the zero-day in Internet Explorer released only a couple of hours ago has put patching on everyone's mind right now, Tenable Security's CTO Ron Gula's post, "How did you test for MS08-067?," was what recently resonated with me.
In Ron's blog, he describes the way two Nessus plug-ins for MS08-067 work. One probes ports on hosts from the network while the other logs into remote hosts and checks for the respective patched files. He then relates the former check as being the primary one used by organizations with immature vulnerability and patch management programs. I've never thought of it that way since I use Nessus regularly and primarily rely on network-based checks, but it makes sense. The difference is that my use falls within the second group of bullets he lists on how organizations use the network check effectively.
Since security groups are almost always separate from sysadmin groups, it makes sense to check patch management processes through network scanning with a vulnerability-scanning tool like Nessus. From my experience, I've found numerous machines that have been "patched" by the sysadmin, but were indeed still vulnerable because the machine had not been rebooted. It pays to have redundancy, especially when it involves something that could lead to exploitation of your systems.
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.