Ah, there is no feeling like seeing your name in the news when drinking your morning coffee... In this piece some Steve Riley, a senior security strategist at Microsoft, decided to "rebute" our recent Black Hat presentations research results.
Mr. Riley had been quoted by ZDnet as saying:
"Her [Joanna Rutkowska] insistence is that you can replace the hypervisor without anybody knowing... Our assertion is that this is incorrect," Riley told the audience. "First of all, to do these attacks you need to become administrator at the root. So that's going to be, on an appropriately configured machine, an exceedingly difficult thing to happen."
Apparently, Mr. Riley has never seen our Black Hat presentations (or slides at least) that he is referring to (oh, wait, that is the typical case with all our "refuters", how come?)...
First, we never said anything about replacing the hypervisor. I really have no idea how this idea was born in Mr. Riley's head? Replacing the hypervisor - that would indeed be insane for us to do!
Second, it is not true that the attacker needs to become an administrator "at the root" (he mean the root partition or administrative domain here I assume). The attack we presented in our second speech, that exploited a heap overflow in the Xen hypervisor FLASK module, could have been conducted from the unprivileged domain, as we demonstrated during the presentation.
Mr. Riley continues with his vision:
"Because you [the attacker] didn't subject your own replacement hypervisor through the thorough design review that ours did, I'll bet your hypervisor is probably not going to implement 100 percent of the functionality as the original one," Riley said. "There will be a gap or two and we will be able to detect that."
Well, if he only took the effort of looking into our slides, he would realize that, in case of XenBluePill, we were slipping it beneath (not replacing!) the original hypervisor, and then run the original one as nested. So, all the functionality of the original hypervisor was preserved.
Mr. Riley also shares some other ground breaking thoughts in this article, but I think we can leave them uncommented ;)
This situation is pretty funny actually - we have here the words and feelings of some Microsoft executive vs. our three technical presentations, all the code that we released for those presentations, and also a few of our demos. Yet, it's apparently still worth getting into the news and reporting what the feeling of Mr. Riley are...
Let me, however, write one more time, that I'm (still) not a Microsoft hater. There are many people at Microsoft that I respect: Brandon Baker, Neil Clift, the LSD guys, Mark Russinovich, and probably a few more that I just haven't had occasion to meet in person or maybe forgot about at the moment. It's thus even more sad that people like Mr. Riley are also associated with Microsoft, even more they are the face of Microsoft for the majority of people. Throwing a party in Vegas and Amsterdam once a year certainly is not enough to change the Microsoft's image in this case...
Interestingly, if Mr. Riley only attended our Xen 0wning Trilogy at Black Hat, then he would notice that we were actually very positive about Hyper-V. Of course, I pointed out that Xen 3.3 certainly has a more secure architecture right now, but I also said that I knew (from talking to some MS engineers from the virtualization group) that Hyper-V is going to implement similar features in the next version(s) and that this is very good. I also prized the fact it has only about 100k LOC (vs. about 300k LOC in Xen 3.3).
So, Mr. Senior Security Strategist, I suggest you do your homework more carefully next time before throwing mud at others and trying to negate the value of their work (and all the efforts of Microsoft's PR people).
On a separate note, I found it quite unprofessional that ZDNet's Liam Tung and Tom Espiner, the authors of the news, didn't ask me for a commentary before publishing this. Not to mention that they also misspelled Rafal's name and forgot to mention about Alex, the third co-author of the presentations.