Super guru Wil Genovese (Trunkful.com) is back to describe an IIS vulnerability that was inserted using a long-known (and patched) CF vulnerability. The Muse will make 2 points. First, if you are hit with this one call us! We will gladly put our shoulder to the wheel and help you dig out. Second, don't forget to patch your servers and keep up on the latest security news. No matter what your chosen platform you need to be vigilant and attentive. Take it away Wil.
First let me point out that the vulnerability that was found has a patch that has been available since January of 2013. So as the Muse said, patch your servers! I first read about this attack in a PC World article titled, PCWorld - Attackers exploited ColdFusion vulnerability to install Microsoft IIS malware. I spent hours reading all the linked websites and blog posts by the security researcher that discovered the IIS Malware (see this Trustwave post) trying in vain to learn the name of said DLL that gets installed, where it gets installed and how to detect the file(s). The few details I found were not completely useful. While I learned the behavior of the malware I never learned how to find the offending DLL or even the file name. I did discover that no existing anti-malware or anti-virus software would detect this rogue DLL. I repeated my futile search every few weeks to see if anything new was being reported.
Since knowing how to locate and expunge such things is part of my job I needed a way to find it, but how? I could search any of the servers at CF Webtools until the cows come home, but if none of them have been hit with this malware I will never find it. What I needed was a server that had been exploited to examine. Over the past year with the slightly larger than usual number of security holes discovered in ColdFusion we've had a few new clients come to us for help in patching and repairing servers. None of the IIS modules on those servers stood out to me as 'unusual', but I wasn't looking directly for this. Finally we had a company come to us for help with a breach.