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Posted by rcbarnett on July 27, 2007.
In many ways vulnerability remediation is like a Track and Field race and the firing of the starters pistol is the public vulnerability announcement. The goal of the race is to be the first one to either exploit or patch a vulnerability. The participants in the race may include; 1) Organizations running the vulnerable application, 2) Attackers looking to exploit the vulnerabilty manually, or 3) The odds on favorite to win the race - an automated worm program. Oraganizations looking to mitigate or patch their systems are the long-shots to win this race. Let's look at a breakdown of the challenges that organizations face:
Unfortunately, many organizations don't realize that they are even in a race! This can be attributed poor monitoring of vulnerability alerts. If you aren't signed up on your Vendor's mail-list or you don't have someone checking out US-CERT or the SANS Internet Storm Center (ISC) daily then you are immediately giving the attackers a 50 yard lead in this race...
If you are running in a relay race, you need to have a baton to pass to each memeber of your team. In this case, the baton is the vendor's security patch. You might be ready, willing and able to start the patching process, however if the vendor doesn't release the patch, you can't really start the race then can you?
Each leg of the relay could be though of as a step in the patching process such as installation on a test host, then pushing the patch out to development, then regression testing and finally out to production. As each phase completes its tasks, it then needs to notify the next group and "hand off the baton" so they can move forward with testing. If this doesn't happen, then the patch will never make it to the finish line - which is when the patches are applied to production hosts. I can't tell you how many times I have seen customers who have patches that make through one or two phases but then just seem to fall off the priority list.
In a relay race, if you step outsite of your lane, then can be disqualified. Similarly, if a security patch ever causes any sort of disruption to normal service then the patch is usually not applied. If there are problems during regression testing, then odds are that the security patch will not make it to the finish line. In the end, functionality will always trump security.
Many organizations want to minimize being disqualified so they take a rather slow, methodical approach to the race and decide just to walk it. These are the organizations who only have quarterly downtime for patching. These companies may get a ribbon for participation but they will never win the race.
What happens if you are not able to apply any patches at all to your web application? Two valid scenarios may be companies who have outsourced the development of their web application and/or who are using an older version of a COTS product where the vendor is no longer providing patches. What options are left for these companies to compete in this race?
So, where does that leave us then? Is there anything that organizations can do the even the playing field in this race? The answer is yes. Virtual Patching can help by providing immediate mitigations to the vulnerability. If an organization were to implement a Virtual Patch on a web application firewall, this will act as a stop-gap measure to prevent remote exploitation of the vulnerability until the actual patch is applied. Using the relay race analogy again, this would be like forcing the attackers to run a steeplechase type of race where there are water pits and 10 ft. tall hurdles in their lane while you are allowed to run a normal race without any obstacles. In this type of scenario, you have a much better chance of beating the attackers to the finish line and protecting your web applications.
If you would like to know more about Virtual Patching, Ivan Ristic and I will be jointly presenting a webcast on this topic very soon -
Date: Wednesday, August 8, 2007
Time: 8AM, Pacific DT
Posted by rcbarnett at July 27, 2007 05:25 PM