The New Path of Least Resistance

By Mike Rothman

It’s hard to believe it has been 10 years since the 9/11 terrorist attacks on the US. I remember that day like it was yesterday. I actually flew into the Boston airport that morning. In hindsight, those attacks opened our eyes to a previously overlooked attack vector – using a passenger jet as a missile. The folks running national security for the US had all sorts of scenarios for how we could be attacked on our own soil, but I’m not sure that vector was on their lists.

It seems we security folks have to start thinking in a similarly orthogonal pattern. Since we started hearing some details of the EMC/RSA breach, and of the attacks on the Comodo and DigiNotar CAs, it has become clear the attackers have been re-thinking their paths of least resistance.

alt textLet me back up a bit. Attackers will follow the path of least resistance to their intended target – they always have. Over the past few years, the path of least resistance has clearly involved exploiting both application and user weakness, rather than breaking technical security measures in network infrastructure. Why break down a door if the nincompoop on the other side will just let you in, and key Internet-facing apps don’t even have locks? That’s what we are seeing in practice.

If an attacker is trying to breach a soft target, the user and application attack vectors remain the path of least resistance for the foreseeable future. The skills gap between the ends is pretty ugly, and not getting better. That’s why we spend so much time focusing on Reacting Faster and Better – it’s pretty much the only way to survive in an age of inevitable compromise.

But what if the target is not soft? By that I mean a well-fortified environment, without the typical user and/or application holes we typically see exploited. A well-segmented and heavily-monitored infrastructure without the standard attack vectors. For example, one of the big defense contractors, who protect the national secrets of the defense/industrial base. Breaking down the doors here is very hard, and in many cases not worth the effort.

So the attackers have identified a new low-resistance path – the security infrastructure protecting those hard targets. It was very clear with the RSA attack. That was all about gaining access to the token seeds and using them to compromise the real targets: US defense contractors. Even if RSA was as well-protected as a defense contractor, breaking into RSA once provided a leg up on all the defense contractors using RSA tokens.

It’s not as clear with the Comodo or DigiNotar attacks. Those seem to be more politically motivated, but still represent an interesting redefinition of the man in the middle attack: compromising the certificate trust chain that identifies legitimate websites.

So what? What impact does this have on day to day operations? Frankly, not much – so many of us are so far behind on basic attempts to block and tackle on the stuff we already know about. But for those hard targets out there, it’s time to expand your threat models to look at the technology that enforces your security controls.

I remember attending a Black Hat session a few years back by Tom Ptacek of Matasano, where he discussed his research into compromising pretty well known IT management technology. That’s the kind of analysis we need looking forward. Push vendors to provide information about how they attack their own products and what they find. But don’t expect much. Vendors do not, as a rule, proactively try to poke holes in their own stuff. And if they do, they don’t would admit weakness by admitting it. So be prepared to do (and fund) much of this work yourself.

But that’s beside the point. It’s time to start thinking that the new path of least resistance may be your security technology. It’s a challenge to the folks that build security products, as well as to those of you who protect hard targets. Who will rise to this challenge?

Photo credit: “Path of Least Resistance” originally uploaded by Billtacular

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Good post, Mike. One consulting team I worked with in the past few years did a really interesting penetration test for a manufacturer of traffic control software (think traffic lights, etc). These folks were really proud of the security they had baked into their application, and wanted to tout it as a selling point to customers, using our pen test data as a catalyst and marketing tool. They still had some flaws, but nothing severe as I remember, and the engagement stood out in my mind for the exact reasons you mention. Very few vendors do this, and you wonder why and how that washes in the security industry. Needs to change, though, for sure.


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