In recent discussions with regards to the WMF vulnerability in Microsoft products there have been may different viewpoints. For example, about whether or not to apply the unofficial patch or wait for one from the vendor. Now it is a somewhat moot point, Microsoft has released their official patch, and it works. Email feedback on our diary posts from the time of the discovery to the time of the MS advisory have been very strongly either for or against some of the stances taken by individual handlers and the Internet Storm Center as a whole. They vary from a hearty thank you, to somewhat less than flattering.

In any case, what it comes down to is the risk to the individual or organization, and how that is managed. A home user may have no compunctions about going ahead and installing the unofficial patch. Or they may choose to wait for the officially sanctioned one, the ease of install and their level of computer knowledge will likely guide them. Corporate or Governmental organizations would have a completely different perspective. Installing a patch can be a major undertaking no matter the source, and their risk management practices would dictate how to proceed. Different organizations will have completely different approaches to determining their risk, and the appropriate actions to mitigate it. Acquiring, testing, and deploying either the official or unofficial patch (or other forms of mitigation) is a significant undertaking no matter the steps taken to arrive at the decision to do so. They may even choose to simply accept the risk and do nothing at all.

The Internet Storm Center is made up of a group of volunteers that have different backgrounds and perspectives on the overall risk of the WMF vulnerability, and the active exploitation seen. The group consensus was that the risk was high enough to warrant raising the Infocon level, and then testing and endorsing the unofficial patch. We are well aware that one size doesn't fit all. At the time it was the only mitigation technique that actually worked. Anti-virus, IDS/IPS do not give adequate protection against this attack and all of its vectors.

We collectively think Microsoft did the right thing in releasing the patch when they did, in advance of their regularly scheduled Tuesday. I think we can all agree that this is a serious issue, and that early patch release is a good thing.  

Many handlers worked long hours on this effort, as did Microsoft and others.

Cheers,
Adrien de Beaupré
ISC handler of the day.
Cinnabar Networks Inc.
http://www.cinnabar.ca