Blogger: Dan Blum

It is no surprise for us to hear loose lips flapping in India about a capability to decrypt Blackberry and other carrier traffic.

After all, we’ve done basic threat analysis for years and it was only months ago that I was brought into a company-wide CISO meeting at a U.S. defense contractor to help them hash out their travel policy for mobile devices. Going into the meeting, I knew their policy restricted taking devices to a list of countries considered dangerous – but there was an exemption for BlackBerries.

Our research uncovered that BlackBerry is pretty secure in most respects. It has transport encryption along with optional password protection, remote kill, disk encryption, and S/MIME encryption. Viruses have not flourished on this functionally limited and closed platform. Few if any third party add on programs are required for additional protection. Nonetheless, I went into the meeting prepared to talk with the CISOs about the risks and security limitations of life on BlackBerry.

Was the BlackBerry exemption reasonable? At the time, BlackBerry transport encryption was not known to have been broken (to be fair, the article listed above still qualifies as rumor, not certainty of breakage). However, I pointed out that it is dangerous to assume well-equipped attackers like military or intelligence organizations can’t crack transport encryption. And even if they haven’t cracked the BlackBerry network and whole disk encryption features, sophisticated adversaries have other attack paths. Check out Neal Stephenson’s excellent book Cryptonomicon for a description of how a talented adversary might “see” your keystrokes and screen images through a motel room wall, for example.

If one of your employees – such as a key scientist, project manager, or executive – is targeted for surveillance and is carrying sensitive data through certain countries, one could argue that he or she had better undergo serious counter-intelligence training.  Learn to spot and shake tails, sneak into dark alleys for that BlackBerry fix. Learn to paper the closet with layers of aluminum foil and send messages in the dark. Defend that BlackBerry with encryption, long passphrases, and kung fu. But unless James Bond is running your company, I doubt this is what your executives have in mind for the next business trip!

Assuming your organization’s lower level employees are like needles in a haystack and won’t be bothered could be an exercise in wishful thinking. It is always possible that nation states are monitoring some or all of the airwaves. Not so long ago the NSA had a massive a covert surveillance program in place. Years before the government was reportedly snarfing up terabytes of emails and crunching them through a program called Carnivore. And of course, selective monitoring of people on watch lists continues on a large scale. This is just the surveillance we know about in the U.S. We suspect there’s more behind the scenes and especially in countries such as China. Even if you train your non-specifically-targeted low level employees to write and speak in search-keyword-free code, the carnivore programs of the world are pretty good at sniffing out those interesting needles – such as descriptions of your business plans, manufacturing processes, and trade secrets.

Sound paranoid? I admit that I don’t know what the probabilities of being targeted or monitored are – just that it can happen. It’s the height of arrogance to believe that a nation state can’t get your information if they’ve targeted it and you’re within their borders. And it’s dangerous to rely on security by obscurity when medium or high consequence information must be protected.

What can be done? If key personnel can't dispense with the BlackBerry (or any other email device) during international travel to those countries where information may be most at risk, they (the users) should limit communications to what they’d feel comfortable uttering over a potentially-monitored telephone call. Controlling incoming communications – messages sent by others – is a harder problem. Until data loss prevention (DLP) products become more contextually sensitive about the travel issues, it may be best not to synchronize the BlackBerry with the overseas user’s home mailbox. Instead, have the user give out a temporary address for the BlackBerry and warn senders to be discreet.

Imagine you're in charge of infiltrating sleeper agents into the United States. The year is 1983, and the proliferation of identity databases is making it increasingly difficult to create fake credentials. Ten years ago, someone could have just shown up in the country and gotten a driver's license, Social Security card and bank account -- possibly using the identity of someone roughly the same age who died as a young child -- but it's getting harder. And you know that trend will only continue. So you decide to grow your own identities.

Call it "identity farming." You invent a handful of infants. You apply for Social Security numbers for them. Eventually, you open bank accounts for them, file tax returns for them, register them to vote, and apply for credit cards in their name. And now, 25 years later, you have a handful of identities ready and waiting for some real people to step into them.

There are some complications, of course. Maybe you need people to sign their name as parents -- or, at least, mothers. Maybe you need to doctors to fill out birth certificates. Maybe you need to fill out paperwork certifying that you're home-schooling these children. You'll certainly want to exercise their financial identity: depositing money into their bank accounts and withdrawing it from ATMs, using their credit cards and paying the bills, and so on. And you'll need to establish some sort of addresses for them, even if it is just a mail drop.

You won't be able to get driver's licenses or photo IDs on their name. That isn't critical, though; in the U.S., more than 20 million adult citizens don't have photo IDs. But other than that, I can't think of any reason why identity farming wouldn't work.

Here's the real question: Do you actually have to show up for any part of your life?

Again, I made this all up. I have no evidence that anyone is actually doing this. It's not something a criminal organization is likely to do; twenty-five years is too distant a payoff horizon. The same logic holds true for terrorist organizations; it's not worth it. It might have been worth it to the KGB -- although perhaps harder to justify after the Soviet Union broke up in 1991 -- and might be an attractive option to existing intelligence adversaries like China.

Immortals could also use this trick to self-perpetuate themselves, inventing their own children and gradually assuming their identity, then killing their parents off. They could even show up for their own driver's license photos, wearing a beard as the father and blue spiked hair as the son. I’m told this is a common idea in Highlander fan fiction.

The point isn't to create another movie plot threat, but to point out the central role that data has taken on in our lives. Previously, I've said that we all have a data shadow that follows us around, and that more and more institutions interact with our data shadows instead of with us. We only intersect with our data shadows once in a while -- when we apply for a driver's license or passport, for example -- and those interactions are authenticated by older, less-secure interactions. The rest of the world assumes that our photo IDs glue us to our data shadows, ignoring the rather flimsy connection between us and our plastic cards. (And, no, REAL-ID won't help.)

It seems to me that our data shadows are becoming increasingly distinct from us, almost with a life of their own. What's important now is our shadows; we're secondary. And as our society relies more and more on these shadows, we might even become unnecessary.

Our data shadows can live a perfectly normal life without us.

This essay previously appeared on Wired.com.

EDITED TO ADD (9/9): Interesting commentary.

Imagine you're in charge of infiltrating sleeper agents into the United States. The year is 1983, and the proliferation of identity databases is making it increasingly difficult to create fake credentials. Ten years ago, someone could have just shown up in the country and gotten a driver's license, Social Security card and bank account -- possibly using the identity of someone roughly the same age who died as a young child -- but it's getting harder. And you know that trend will only continue. So you decide to grow your own identities.

Call it "identity farming." You invent a handful of infants. You apply for Social Security numbers for them. Eventually, you open bank accounts for them, file tax returns for them, register them to vote, and apply for credit cards in their name. And now, 25 years later, you have a handful of identities ready and waiting for some real people to step into them.

There are some complications, of course. Maybe you need people to sign their name as parents -- or, at least, mothers. Maybe you need to doctors to fill out birth certificates. Maybe you need to fill out paperwork certifying that you're home-schooling these children. You'll certainly want to exercise their financial identity: depositing money into their bank accounts and withdrawing it from ATMs, using their credit cards and paying the bills, and so on. And you'll need to establish some sort of addresses for them, even if it is just a mail drop.

You won't be able to get driver's licenses or photo IDs on their name. That isn't critical, though; in the U.S., more than 20 million adult citizens don't have photo IDs. But other than that, I can't think of any reason why identity farming wouldn't work.

Here's the real question: Do you actually have to show up for any part of your life?

Again, I made this all up. I have no evidence that anyone is actually doing this. It's not something a criminal organization is likely to do; twenty-five years is too distant a payoff horizon. The same logic holds true for terrorist organizations; it's not worth it. It might have been worth it to the KGB -- although perhaps harder to justify after the Soviet Union broke up in 1991 -- and might be an attractive option to existing intelligence adversaries like China.

Immortals could also use this trick to self-perpetuate themselves, inventing their own children and gradually assuming their identity, then killing their parents off. They could even show up for their own driver's license photos, wearing a beard as the father and blue spiked hair as the son. I’m told this is a common idea in Highlander fan fiction.

The point isn't to create another movie plot threat, but to point out the central role that data has taken on in our lives. Previously, I've said that we all have a data shadow that follows us around, and that more and more institutions interact with our data shadows instead of with us. We only intersect with our data shadows once in a while -- when we apply for a driver's license or passport, for example -- and those interactions are authenticated by older, less-secure interactions. The rest of the world assumes that our photo IDs glue us to our data shadows, ignoring the rather flimsy connection between us and our plastic cards. (And, no, REAL-ID won't help.)

It seems to me that our data shadows are becoming increasingly distinct from us, almost with a life of their own. What's important now is our shadows; we're secondary. And as our society relies more and more on these shadows, we might even become unnecessary.

Our data shadows can live a perfectly normal life without us.

---

Bruce Schneier is Chief Security Technology Officer of BT, and author of Beyond Fear: Thinking Sensibly About Security in an Uncertain World.

Our paper has now been announced as a runner-up for the Privacy Enhancing Technologies Award. The prize is presented annually, for research which makes an outstanding contribution to the field. Microsoft, the sponsor of the award, have further details and summaries of the papers in their press release.

Congratulations to the winners, Arvind Narayanan and Vitaly Shmatikov, for “Robust De-Anonymization of Large Sparse Datasets”; and the other runner-ups, Mira Belenkiy, Melissa Chase, C. Chris Erway, John Jannotti, Alptekin Küpçü, Anna Lysyanskaya and Erich Rachlin, for “Making P2P Accountable without Losing Privacy”.

If someone is simultaneously watching a user’s traffic as it enters and leaves the network, it is possible to de-anonymise the communication. This could occur if the first and last node for a connection is controlled by the same person. Tor takes some steps to avoid this possibility e.g. no two computers on the same /16 network may be chosen for each connection. However, someone with access to several networks could circumvent this measure.

Not only is route selection critical for security, but it’s also a significant performance factor. Tor nodes vary dramatically in their capacity, mainly due to their network connections. If all nodes were chosen with equal likelihood, the slower ones would cripple the network. This is why Tor weights the selection probability for a node proportional to its contribution to the network bandwidth.

Because of the dual importance of route selection, there are a number of proposals which offer an alternative to Tor’s bandwidth-weighted algorithm. Later this week at PETS I’ll be presenting my paper, co-authored with Robert N.M. Watson, “Metrics for security and performance in low-latency anonymity systems”. In this paper, we examine several route selection algorithms and evaluate their security and performance.

Intuitively, a route selection algorithm which weights all nodes equally appears the most secure because an attacker can’t make their node count any more than the others. This has been formalized by two measures: Gini coefficient and entropy. In fact the reality is more complex — uniform node selection resists attackers with lots of bandwidth, whereas bandwidth-weighting is better against attackers with lots of nodes.

Our paper explores the probability of path compromise of different route selection algorithms, when under attack by a range of different adversaries. We find that none of the proposals are optimal against all adversaries, and so summarizing effective security in terms of a single figure is not feasible. We also model the performance of the schemes and show that bandwidth-weighting offers both low latency and high resistance to attack by bandwidth-constrained adversaries.

Disappointingly, the author sprinkles the usual super-secret uber-hacker spin throughout the article to make the Red Team seem mysterious and exclusive, with untouchable talent. It’s a little misleading. For starters, there’s the predictable question about success rates:

I’d heard from one of the Department of Defense clients who had previously worked with the NSA red team that OWNSAVAOG and his team had a success rate of close to 100 percent. “We don’t keep statistics on that,” OWNSAVAOG insisted when I pressed him on an internal measuring stick.

This is one of those statements that is difficult for the average reader to interpret. It’s intended to make the team sound like a crack squad of hackers, but in reality it’s the same statistic that every security consultancy cites during sales calls. The truth is, there’s a lot of wiggle room on what is considered “getting in” to the target. For example, some would say that brute forcing an FTP server and downloading some FOUO (For Official Use Only) documents constitutes penetrating the target. Others would disagree.

How about personnel? I thought this was an englightening and accurate statement from the unnamed NSA source:

And like any good geek at a desk talking to a guy with a really cool job, I wondered just where the NSA finds the members of its superhacker squad. “The bulk is military personnel, civilian government employees and a small cadre of contractors,” OWNSAVAOG says. The military guys mainly conduct the ops (the actual breaking and entering stuff), while the civilians and contractors mainly write code to support their endeavors. For those of you looking for a gig in the ultrasecret world of red teaming, this top hacker says the ideal profile is someone with “technical skills, an adversarial mind-set, perseverance and imagination.”

He basically admits that the team consists mostly of people who “run the tools” and only a handful that actually write the tools or do anything cutting-edge. It shouldn’t be that surprising; just as in any large consulting organization, you have some people who run scanners/tools and aren’t expected to be terribly analytical. While the Red Team almost certainly has some superstars, on the whole it is similar in both skillset and composition to a typical consultancy or enterprise security team.

In terms of attracting and retaining top talent, the Red Team faces the same challenges as the rest of the information security industry, with the built-in disadvantage of the government pay scale. If that wasn’t bad enough, they also have to compete with themselves (i.e. the rest of the NSA) for already scarce resources. Given these challenges, how could one realistically expect the Red Team to be as advanced as the article portrays?

Finally, let’s dispel the “super-secret” notion — unless things have changed significantly, the majority of Red Team operations are unclassified. Granted, detailed information is guarded, but you can find reports summarizing past operations if you dig around a bit. One would expect that an operation intended to be truly secretive would never make its way into Google search results.

I want to conclude by saying that this post is not intended to cast the Red Team itself in a negative light. I enjoyed my time there and had the opportunity to work with some smart people. The Red Team’s goals are worthy and noble; clearly, state-sponsored cyberterrorism is a growing concern and as a country we should be as prepared as possible. But realize that we have a long way to go.