Entries Tagged "essays"

Page 28 of 48

Data at Rest vs. Data in Motion

For a while now, I’ve pointed out that cryptography is singularly ill-suited to solve the major network security problems of today: denial-of-service attacks, website defacement, theft of credit card numbers, identity theft, viruses and worms, DNS attacks, network penetration, and so on.

Cryptography was invented to protect communications: data in motion. This is how cryptography was used throughout most of history, and this is how the militaries of the world developed the science. Alice was the sender, Bob the receiver, and Eve the eavesdropper. Even when cryptography was used to protect stored data—data at rest—it was viewed as a form of communication. In “Applied Cryptography,” I described encrypting stored data in this way: “a stored message is a way for someone to communicate with himself through time.” Data storage was just a subset of data communication.

In modern networks, the difference is much more profound. Communications are immediate and instantaneous. Encryption keys can be ephemeral, and systems like the STU-III telephone can be designed such that encryption keys are created at the beginning of a call and destroyed as soon as the call is completed. Data storage, on the other hand, occurs over time. Any encryption keys must exist as long as the encrypted data exists. And storing those keys becomes as important as storing the unencrypted data was. In a way, encryption doesn’t reduce the number of secrets that must be stored securely; it just makes them much smaller.

Historically, the reason key management worked for stored data was that the key could be stored in a secure location: the human brain. People would remember keys and, barring physical and emotional attacks on the people themselves, would not divulge them. In a sense, the keys were stored in a “computer” that was not attached to any network. And there they were safe.

This whole model falls apart on the Internet. Much of the data stored on the Internet is only peripherally intended for use by people; it’s primarily intended for use by other computers. And therein lies the problem. Keys can no longer be stored in people’s brains. They need to be stored on the same computer, or at least the network, that the data resides on. And that is much riskier.

Let’s take a concrete example: credit card databases associated with websites. Those databases are not encrypted because it doesn’t make any sense. The whole point of storing credit card numbers on a website is so it’s accessible—so each time I buy something, I don’t have to type it in again. The website needs to dynamically query the database and retrieve the numbers, millions of times a day. If the database were encrypted, the website would need the key. But if the key were on the same network as the data, what would be the point of encrypting it? Access to the website equals access to the database in either case. Security is achieved by good access control on the website and database, not by encrypting the data.

The same reasoning holds true elsewhere on the Internet as well. Much of the Internet’s infrastructure happens automatically, without human intervention. This means that any encryption keys need to reside in software on the network, making them vulnerable to attack. In many cases, the databases are queried so often that they are simply left in plaintext, because doing otherwise would cause significant performance degradation. Real security in these contexts comes from traditional computer security techniques, not from cryptography.

Cryptography has inherent mathematical properties that greatly favor the defender. Adding a single bit to the length of a key adds only a slight amount of work for the defender, but doubles the amount of work the attacker has to do. Doubling the key length doubles the amount of work the defender has to do (if that—I’m being approximate here), but increases the attacker’s workload exponentially. For many years, we have exploited that mathematical imbalance.

Computer security is much more balanced. There’ll be a new attack, and a new defense, and a new attack, and a new defense. It’s an arms race between attacker and defender. And it’s a very fast arms race. New vulnerabilities are discovered all the time. The balance can tip from defender to attacker overnight, and back again the night after. Computer security defenses are inherently very fragile.

Unfortunately, this is the model we’re stuck with. No matter how good the cryptography is, there is some other way to break into the system. Recall how the FBI read the PGP-encrypted email of a suspected Mafia boss several years ago. They didn’t try to break PGP; they simply installed a keyboard sniffer on the target’s computer. Notice that SSL- and TLS-encrypted web communications are increasingly irrelevant in protecting credit card numbers; criminals prefer to steal them by the hundreds of thousands from back-end databases.

On the Internet, communications security is much less important than the security of the endpoints. And increasingly, we can’t rely on cryptography to solve our security problems.

This essay originally appeared on DarkReading. I wrote it in 2006, but lost it on my computer for four years. I hate it when that happens.

EDITED TO ADD (7/14): As several readers pointed out, I overstated my case when I said that encrypting credit card databases, or any database in constant use, is useless. In fact, there is value in encrypting those databases, especially if the encryption appliance is separate from the database server. In this case, the attacker has to steal both the encryption key and the database. That’s a harder hacking problem, and this is why credit-card database encryption is mandated within the PCI security standard. Given how good encryption performance is these days, it’s a smart idea. But while encryption makes it harder to steal the data, it is only harder in a computer-security sense and not in a cryptography sense.

Posted on June 30, 2010 at 12:53 PMView Comments

Hiring Hackers

Any essay on hiring hackers quickly gets bogged down in definitions. What is a hacker, and how is he different from a cracker? I have my own definitions, but I’d rather define the issue more specifically: Would you hire someone convicted of a computer crime to fill a position of trust in your computer network? Or, more generally, would you hire someone convicted of a crime for a job related to that crime?

The answer, of course, is “it depends.” It depends on the specifics of the crime. It depends on the ethics involved. It depends on the recidivism rate of the type of criminal. It depends a whole lot on the individual.

Would you hire a convicted pedophile to work at a day care center? Would you hire Bernie Madoff to manage your investment fund? The answer is almost certainly no to those two—but you might hire a convicted bank robber to consult on bank security. You might hire someone who was convicted of false advertising to write ad copy for your next marketing campaign. And you might hire someone who ran a chop shop to fix your car. It depends on the person and the crime.

It can get even murkier. Would you hire a CIA-trained assassin to be a bodyguard? Would you put a general who led a successful attack in charge of defense? What if they were both convicted of crimes in whatever country they were operating in? There are different legal and ethical issues, to be sure, but in both cases the people learned a certain set of skills regarding offense that could be transferable to defense.

Which brings us back to computers. Hacking is primarily a mindset: a way of thinking about security. Its primary focus is in attacking systems, but it’s invaluable to the defense of those systems as well. Because computer systems are so complex, defending them often requires people who can think like attackers.

Admittedly, there’s a difference between thinking like an attacker and acting like a criminal, and between researching vulnerabilities in fielded systems and exploiting those vulnerabilities for personal gain. But there is a huge variability in computer crime convictions, and—at least in the early days—many hacking convictions were unjust and unfair. And there’s also a difference between someone’s behavior as a teenager and his behavior later in life. Additionally, there might very well be a difference between someone’s behavior before and after a hacking conviction. It all depends on the person.

An employer’s goal should be to hire moral and ethical people with the skill set required to do the job. And while a hacking conviction is certainly a mark against a person, it isn’t always grounds for complete non-consideration.

“We don’t hire hackers” and “we don’t hire felons” are coarse generalizations, in the same way that “we only hire people with this or that security certification” is. They work—you’re less likely to hire the wrong person if you follow them—but they’re both coarse and flawed. Just as all potential employees with certifications aren’t automatically good hires, all potential employees with hacking convictions aren’t automatically bad hires. Sure, it’s easier to hire people based on things you can learn from checkboxes, but you won’t get the best employees that way. It’s far better to look at the individual, and put those check boxes into context. But we don’t always have time to do that.

Last winter, a Minneapolis attorney who works to get felons a fair shake after they served their time told of a sign he saw: “Snow shovelers wanted. Felons need not apply.” It’s not good for society if felons who have served their time can’t even get jobs shoveling snow.

This essay previously appeared in Information Security as the first half of a point-counterpoint with Marcus Ranum. Marcus’s half is here.

Posted on June 10, 2010 at 6:34 AMView Comments

Worst-Case Thinking

At a security conference recently, the moderator asked the panel of distinguished cybersecurity leaders what their nightmare scenario was. The answers were the predictable array of large-scale attacks: against our communications infrastructure, against the power grid, against the financial system, in combination with a physical attack.

I didn’t get to give my answer until the afternoon, which was: “My nightmare scenario is that people keep talking about their nightmare scenarios.”

There’s a certain blindness that comes from worst-case thinking. An extension of the precautionary principle, it involves imagining the worst possible outcome and then acting as if it were a certainty. It substitutes imagination for thinking, speculation for risk analysis, and fear for reason. It fosters powerlessness and vulnerability and magnifies social paralysis. And it makes us more vulnerable to the effects of terrorism.

Worst-case thinking means generally bad decision making for several reasons. First, it’s only half of the cost-benefit equation. Every decision has costs and benefits, risks and rewards. By speculating about what can possibly go wrong, and then acting as if that is likely to happen, worst-case thinking focuses only on the extreme but improbable risks and does a poor job at assessing outcomes.

Second, it’s based on flawed logic. It begs the question by assuming that a proponent of an action must prove that the nightmare scenario is impossible.

Third, it can be used to support any position or its opposite. If we build a nuclear power plant, it could melt down. If we don’t build it, we will run short of power and society will collapse into anarchy. If we allow flights near Iceland’s volcanic ash, planes will crash and people will die. If we don’t, organs won’t arrive in time for transplant operations and people will die. If we don’t invade Iraq, Saddam Hussein might use the nuclear weapons he might have. If we do, we might destabilize the Middle East, leading to widespread violence and death.

Of course, not all fears are equal. Those that we tend to exaggerate are more easily justified by worst-case thinking. So terrorism fears trump privacy fears, and almost everything else; technology is hard to understand and therefore scary; nuclear weapons are worse than conventional weapons; our children need to be protected at all costs; and annihilating the planet is bad. Basically, any fear that would make a good movie plot is amenable to worst-case thinking.

Fourth and finally, worst-case thinking validates ignorance. Instead of focusing on what we know, it focuses on what we don’t know—and what we can imagine.

Remember Defense Secretary Rumsfeld’s quote? “Reports that say that something hasn’t happened are always interesting to me, because as we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns—the ones we don’t know we don’t know.” And this: “the absence of evidence is not evidence of absence.” Ignorance isn’t a cause for doubt; when you can fill that ignorance with imagination, it can be a call to action.

Even worse, it can lead to hasty and dangerous acts. You can’t wait for a smoking gun, so you act as if the gun is about to go off. Rather than making us safer, worst-case thinking has the potential to cause dangerous escalation.

The new undercurrent in this is that our society no longer has the ability to calculate probabilities. Risk assessment is devalued. Probabilistic thinking is repudiated in favor of “possibilistic thinking“: Since we can’t know what’s likely to go wrong, let’s speculate about what can possibly go wrong.

Worst-case thinking leads to bad decisions, bad systems design, and bad security. And we all have direct experience with its effects: airline security and the TSA, which we make fun of when we’re not appalled that they’re harassing 93-year-old women or keeping first graders off airplanes. You can’t be too careful!

Actually, you can. You can refuse to fly because of the possibility of plane crashes. You can lock your children in the house because of the possibility of child predators. You can eschew all contact with people because of the possibility of hurt. Steven Hawking wants to avoid trying to communicate with aliens because they might be hostile; does he want to turn off all the planet’s television broadcasts because they’re radiating into space? It isn’t hard to parody worst-case thinking, and at its extreme it’s a psychological condition.

Frank Furedi, a sociology professor at the University of Kent, writes: “Worst-case thinking encourages society to adopt fear as one of the dominant principles around which the public, the government and institutions should organize their life. It institutionalizes insecurity and fosters a mood of confusion and powerlessness. Through popularizing the belief that worst cases are normal, it incites people to feel defenseless and vulnerable to a wide range of future threats.”

Even worse, it plays directly into the hands of terrorists, creating a population that is easily terrorized—even by failed terrorist attacks like the Christmas Day underwear bomber and the Times Square SUV bomber.

When someone is proposing a change, the onus should be on them to justify it over the status quo. But worst-case thinking is a way of looking at the world that exaggerates the rare and unusual and gives the rare much more credence than it deserves.

It isn’t really a principle; it’s a cheap trick to justify what you already believe. It lets lazy or biased people make what seem to be cogent arguments without understanding the whole issue. And when people don’t need to refute counterarguments, there’s no point in listening to them.

This essay was originally published on CNN.com, although they stripped out all the links.

Posted on May 13, 2010 at 6:53 AMView Comments

Why Aren't There More Terrorist Attacks?

As the details of the Times Square car bomb attempt emerge in the wake of Faisal Shahzad’s arrest Monday night, one thing has already been made clear: Terrorism is fairly easy. All you need is a gun or a bomb, and a crowded target. Guns are easy to buy. Bombs are easy to make. Crowded targets—not only in New York, but all over the country—are easy to come by. If you’re willing to die in the aftermath of your attack, you could launch a pretty effective terrorist attack with a few days of planning, maybe less.

But if it’s so easy, why aren’t there more terrorist attacks like the failed car bomb in New York’s Times Square? Or the terrorist shootings in Mumbai? Or the Moscow subway bombings? After the enormous horror and tragedy of 9/11, why have the past eight years been so safe in the U.S.?

There are actually several answers to this question. One, terrorist attacks are harder to pull off than popular imagination—and the movies—lead everyone to believe. Two, there are far fewer terrorists than the political rhetoric of the past eight years leads everyone to believe. And three, random minor terrorist attacks don’t serve Islamic terrorists’ interests right now.

Hard to Pull Off

Terrorism sounds easy, but the actual attack is the easiest part.

Putting together the people, the plot and the materials is hard. It’s hard to sneak terrorists into the U.S. It’s hard to grow your own inside the U.S. It’s hard to operate; the general population, even the Muslim population, is against you.

Movies and television make terrorist plots look easier than they are. It’s hard to hold conspiracies together. It’s easy to make a mistake. Even 9/11, which was planned before the climate of fear that event engendered, just barely succeeded. Today, it’s much harder to pull something like that off without slipping up and getting arrested.

Few Terrorists

But even more important than the difficulty of executing a terrorist attack, there aren’t a lot of terrorists out there. Al-Qaida isn’t a well-organized global organization with movie-plot-villain capabilities; it’s a loose collection of people using the same name. Despite the post-9/11 rhetoric, there isn’t a terrorist cell in every major city. If you think about the major terrorist plots we’ve foiled in the U.S.—the JFK bombers, the Fort Dix plotters—they were mostly amateur terrorist wannabes with no connection to any sort of al-Qaida central command, and mostly no ability to effectively carry out the attacks they planned.

The successful terrorist attacks—the Fort Hood shooter, the guy who flew his plane into the Austin IRS office, the anthrax mailer—were largely nut cases operating alone. Even the unsuccessful shoe bomber, and the equally unsuccessful Christmas Day underwear bomber, had minimal organized help—and that help originated outside the U.S.

Terrorism doesn’t occur without terrorists, and they are far rarer than popular opinion would have it.

Small Attacks Aren’t Enough

Lastly, and perhaps most subtly, there’s not a lot of value in unspectacular terrorism anymore.

If you think about it, terrorism is essentially a PR stunt. The death of innocents and the destruction of property isn’t the goal of terrorism; it’s just the tactic used. And acts of terrorism are intended for two audiences: for the victims, who are supposed to be terrorized as a result, and for the allies and potential allies of the terrorists, who are supposed to give them more funding and generally support their efforts.

An act of terrorism that doesn’t instill terror in the target population is a failure, even if people die. And an act of terrorism that doesn’t impress the terrorists’ allies is not very effective, either.

Fortunately for us and unfortunately for the terrorists, 9/11 upped the stakes. It’s no longer enough to blow up something like the Oklahoma City Federal Building. Terrorists need to blow up airplanes or the Brooklyn Bridge or the Sears Tower or JFK airport—something big to impress the folks back home. Small no-name targets just don’t cut it anymore.

Note that this is very different than terrorism by an occupied population: the IRA in Northern Ireland, Iraqis in Iraq, Palestinians in Israel. Setting aside the actual politics, all of these terrorists believe they are repelling foreign invaders. That’s not the situation here in the U.S.

So, to sum up: If you’re just a loner wannabe who wants to go out with a bang, terrorism is easy. You’re more likely to get caught if you take a long time to plan or involve a bunch of people, but you might succeed. If you’re a representative of al-Qaida trying to make a statement in the U.S., it’s much harder. You just don’t have the people, and you’re probably going to slip up and get caught.

This essay originally appeared on AOL News.

EDITED TO ADD (5/5): A similar sentiment about the economic motivations of terrorists.

Posted on May 5, 2010 at 7:09 AMView Comments

Preventing Terrorist Attacks in Crowded Areas

On the New York Times Room for Debate Blog, I—along with several other people—was asked about how to prevent terrorist attacks in crowded areas. This is my response.

In the wake of Saturday’s failed Times Square car bombing, it’s natural to ask how we can prevent this sort of thing from happening again. The answer is stop focusing on the specifics of what actually happened, and instead think about the threat in general.

Think about the security measures commonly proposed. Cameras won’t help. They don’t prevent terrorist attacks, and their forensic value after the fact is minimal. In the Times Square case, surely there’s enough other evidence—the car’s identification number, the auto body shop the stolen license plates came from, the name of the fertilizer store—to identify the guy. We will almost certainly not need the camera footage. The images released so far, like the images in so many other terrorist attacks, may make for exciting television, but their value to law enforcement officers is limited.

Check points won’t help, either. You can’t check everybody and everything. There are too many people to check, and too many train stations, buses, theaters, department stores and other places where people congregate. Patrolling guards, bomb-sniffing dogs, chemical and biological weapons detectors: they all suffer from similar problems. In general, focusing on specific tactics or defending specific targets doesn’t make sense. They’re inflexible; possibly effective if you guess the plot correctly, but completely ineffective if you don’t. At best, the countermeasures just force the terrorists to make minor changes in their tactic and target.

It’s much smarter to spend our limited counterterrorism resources on measures that don’t focus on the specific. It’s more efficient to spend money on investigating and stopping terrorist attacks before they happen, and responding effectively to any that occur. This approach works because it’s flexible and adaptive; it’s effective regardless of what the bad guys are planning for next time.

After the Christmas Day airplane bombing attempt, I was asked how we can better protect our airplanes from terrorist attacks. I pointed out that the event was a security success—the plane landed safely, nobody was hurt, a terrorist was in custody—and that the next attack would probably have nothing to do with explosive underwear. After the Moscow subway bombing, I wrote that overly specific security countermeasures like subway cameras and sensors were a waste of money.

Now we have a failed car bombing in Times Square. We can’t protect against the next imagined movie-plot threat. Isn’t it time to recognize that the bad guys are flexible and adaptive, and that we need the same quality in our countermeasures?

I know, nothing I haven’t said many times before.

Steven Simon likes cameras, although his arguments are more movie-plot than real. Michael Black, Noah Shachtman, Michael Tarr, and Jeffrey Rosen all write about the limitations of security cameras. Paul Ekman wants more people. And Richard Clarke has a nice essay about how we shouldn’t panic.

Posted on May 4, 2010 at 1:31 PMView Comments

New York and the Moscow Subway Bombing

People intent on preventing a Moscow-style terrorist attack against the New York subway system are proposing a range of expensive new underground security measures, some temporary and some permanent.

They should save their money – and instead invest every penny they’re considering pouring into new technologies into intelligence and old-fashioned policing.

Intensifying security at specific stations only works against terrorists who aren’t smart enough to move to another station. Cameras are useful only if all the stars align: The terrorists happen to walk into the frame, the video feeds are being watched in real time and the police can respond quickly enough to be effective. They’re much more useful after an attack, to figure out who pulled it off.

Installing biological and chemical detectors requires similarly implausible luck – plus a terrorist plot that includes the specific biological or chemical agent that is being detected.

What all these misguided reactions have in common is that they’re based on “movie-plot threats”: overly specific attack scenarios. They fill our imagination vividly, in full color with rich detail. Before long, we’re envisioning an entire story line, with or without Bruce Willis saving the day. And we’re scared.

It’s not that movie-plot threats are not worth worrying about. It’s that each one – Moscow’s subway attack, the bombing of the Oklahoma City federal building, etc. – is too specific. These threats are infinite, and the bad guys can easily switch among them.

New York has thousands of possible targets, and there are dozens of possible tactics. Implementing security against movie-plot threats is only effective if we correctly guess which specific threat to protect against. That’s unlikely.

A far better strategy is to spend our limited counterterrorism resources on investigation and intelligence – and on emergency response. These measures don’t hinge on any specific threat; they don’t require us to guess the tactic or target correctly. They’re effective in a variety of circumstances, even nonterrorist ones.

The result may not be flashy or outwardly reassuring – as are pricey new scanners in airports. But the strategy will save more lives.

The 2006 arrest of the liquid bombers – who wanted to detonate liquid explosives to be brought onboard airliners traveling from England to North America – serves as an excellent example. The plotters were arrested in their London apartments, and their attack was foiled before they ever got to the airport.

It didn’t matter if they were using liquids or solids or gases. It didn’t even matter if they were targeting airports or shopping malls or theaters. It was a straightforward, although hardly simple, matter of following leads.

Gimmicky security measures are tempting – but they’re distractions we can’t afford. The Christmas Day bomber chose his tactic because it would circumvent last year’s security measures, and the next attacker will choose his tactic – and target – according to similar criteria. Spend money on cameras and guards in the subways, and the terrorists will simply modify their plot to render those countermeasures ineffective.

Humans are a species of storytellers, and the Moscow story has obvious parallels in New York. When we read the word “subway,” we can’t help but think about the system we use every day. This is a natural response, but it doesn’t make for good public policy. We’d all be safer if we rose above the simple parallels and the need to calm our fears with expensive and seductive new technologies – and countered the threat the smart way.

This essay originally appeared in the New York Daily News.

Posted on April 7, 2010 at 8:52 AMView Comments

Privacy and Control

In January Facebook Chief Executive, Mark Zuckerberg, declared the age of privacy to be over. A month earlier, Google Chief Eric Schmidt expressed a similar sentiment. Add Scott McNealy’s and Larry Ellison’s comments from a few years earlier, and you’ve got a whole lot of tech CEOs proclaiming the death of privacy—especially when it comes to young people.

It’s just not true. People, including the younger generation, still care about privacy. Yes, they’re far more public on the Internet than their parents: writing personal details on Facebook, posting embarrassing photos on Flickr and having intimate conversations on Twitter. But they take steps to protect their privacy and vociferously complain when they feel it violated. They’re not technically sophisticated about privacy and make mistakes all the time, but that’s mostly the fault of companies and Web sites that try to manipulate them for financial gain.

To the older generation, privacy is about secrecy. And, as the Supreme Court said, once something is no longer secret, it’s no longer private. But that’s not how privacy works, and it’s not how the younger generation thinks about it. Privacy is about control. When your health records are sold to a pharmaceutical company without your permission; when a social-networking site changes your privacy settings to make what used to be visible only to your friends visible to everyone; when the NSA eavesdrops on everyone’s e-mail conversations—your loss of control over that information is the issue. We may not mind sharing our personal lives and thoughts, but we want to control how, where and with whom. A privacy failure is a control failure.

People’s relationship with privacy is socially complicated. Salience matters: People are more likely to protect their privacy if they’re thinking about it, and less likely to if they’re thinking about something else. Social-networking sites know this, constantly reminding people about how much fun it is to share photos and comments and conversations while downplaying the privacy risks. Some sites go even further, deliberately hiding information about how little control—and privacy—users have over their data. We all give up our privacy when we’re not thinking about it.

Group behavior matters; we’re more likely to expose personal information when our peers are doing it. We object more to losing privacy than we value its return once it’s gone. Even if we don’t have control over our data, an illusion of control reassures us. And we are poor judges of risk. All sorts of academic research backs up these findings.

Here’s the problem: The very companies whose CEOs eulogize privacy make their money by controlling vast amounts of their users’ information. Whether through targeted advertising, cross-selling or simply convincing their users to spend more time on their site and sign up their friends, more information shared in more ways, more publicly means more profits. This means these companies are motivated to continually ratchet down the privacy of their services, while at the same time pronouncing privacy erosions as inevitable and giving users the illusion of control.

You can see these forces in play with Google‘s launch of Buzz. Buzz is a Twitter-like chatting service, and when Google launched it in February, the defaults were set so people would follow the people they corresponded with frequently in Gmail, with the list publicly available. Yes, users could change these options, but—and Google knew this—changing options is hard and most people accept the defaults, especially when they’re trying out something new. People were upset that their previously private e-mail contacts list was suddenly public. A Federal Trade Commission commissioner even threatened penalties. And though Google changed its defaults, resentment remained.

Facebook tried a similar control grab when it changed people’s default privacy settings last December to make them more public. While users could, in theory, keep their previous settings, it took an effort. Many people just wanted to chat with their friends and clicked through the new defaults without realizing it.

Facebook has a history of this sort of thing. In 2006 it introduced News Feeds, which changed the way people viewed information about their friends. There was no true privacy change in that users could not see more information than before; the change was in control—or arguably, just in the illusion of control. Still, there was a large uproar. And Facebook is doing it again; last month, the company announced new privacy changes that will make it easier for it to collect location data on users and sell that data to third parties.

With all this privacy erosion, those CEOs may actually be right—but only because they’re working to kill privacy. On the Internet, our privacy options are limited to the options those companies give us and how easy they are to find. We have Gmail and Facebook accounts because that’s where we socialize these days, and it’s hard—especially for the younger generation—to opt out. As long as privacy isn’t salient, and as long as these companies are allowed to forcibly change social norms by limiting options, people will increasingly get used to less and less privacy. There’s no malice on anyone’s part here; it’s just market forces in action. If we believe privacy is a social good, something necessary for democracy, liberty and human dignity, then we can’t rely on market forces to maintain it. Broad legislation protecting personal privacy by giving people control over their personal data is the only solution.

This essay originally appeared on Forbes.com.

EDITED TO ADD (4/13): Google responds. And another essay on the topic.

Posted on April 6, 2010 at 7:47 AMView Comments

Should the Government Stop Outsourcing Code Development?

Information technology is increasingly everywhere, and it’s the same technologies everywhere. The same operating systems are used in corporate and government computers. The same software controls critical infrastructure and home shopping. The same networking technologies are used in every country. The same digital infrastructure underpins the small and the large, the important and the trivial, the local and the global; the same vendors, the same standards, the same protocols, the same applications.

With all of this sameness, you’d think these technologies would be designed to the highest security standard, but they’re not. They’re designed to the lowest or, at best, somewhere in the middle. They’re designed sloppily, in an ad hoc manner, with efficiency in mind. Security is a requirement, more or less, but it’s a secondary priority. It’s far less important than functionality, and security is what gets compromised when schedules get tight.

Should the government—ours, someone else’s?—stop outsourcing code development? That’s the wrong question to ask. Code isn’t magically more secure when it’s written by someone who receives a government paycheck than when it’s written by someone who receives a corporate paycheck. It’s not magically less secure when it’s written by someone who speaks a foreign language, or is paid by the hour instead of by salary. Writing all your code in-house isn’t even a viable option anymore; we’re all stuck with software written by who-knows-whom in who-knows-which-country. And we need to figure out how to get security from that.

The traditional solution has been defense in depth: layering one mediocre security measure on top of another mediocre security measure. So we have the security embedded in our operating system and applications software, the security embedded in our networking protocols, and our additional security products such as antivirus and firewalls. We hope that whatever security flaws—either found and exploited, or deliberately inserted—there are in one layer are counteracted by the security in another layer, and that when they’re not, we can patch our systems quickly enough to avoid serious long-term damage. That is a lousy solution when you think about it, but we’ve been more-or-less managing with it so far.

Bringing all software—and hardware, I suppose—development in-house under some misconception that proximity equals security is not a better solution. What we need is to improve the software development process, so we can have some assurance that our software is secure—regardless of what coder, employed by what company, and living in what country, writes it. The key word here is “assurance.”

Assurance is less about developing new security techniques than about using the ones we already have. It’s all the things described in books on secure coding practices. It’s what Microsoft is trying to do with its Security Development Lifecycle. It’s the Department of Homeland Security’s Build Security In program. It’s what every aircraft manufacturer goes through before it fields a piece of avionics software. It’s what the NSA demands before it purchases a piece of security equipment. As an industry, we know how to provide security assurance in software and systems. But most of the time, we don’t care; commercial software, as insecure as it is, is good enough for most purposes.

Assurance is expensive, in terms of money and time, for both the process and the documentation. But the NSA needs assurance for critical military systems and Boeing needs it for its avionics. And the government needs it more and more: for voting machines, for databases entrusted with our personal information, for electronic passports, for communications systems, for the computers and systems controlling our critical infrastructure. Assurance requirements should be more common in government IT contracts.

The software used to run our critical infrastructure—government, corporate, everything—isn’t very secure, and there’s no hope of fixing it anytime soon. Assurance is really our only option to improve this, but it’s expensive and the market doesn’t care. Government has to step in and spend the money where its requirements demand it, and then we’ll all benefit when we buy the same software.

This essay first appeared in Information Security, as the second part of a point-counterpoint with Marcus Ranum. You can read Marcus’s essay there as well.

Posted on March 31, 2010 at 6:54 AMView Comments

Security and Function Creep

Security is rarely static. Technology changes both security systems and attackers. But there’s something else that changes security’s cost/benefit trade-off: how the underlying systems being secured are used. Far too often we build security for one purpose, only to find it being used for another purpose—one it wasn’t suited for in the first place. And then the security system has to play catch-up.

Take driver’s licenses, for example. Originally designed to demonstrate a credential—the ability to drive a car—they looked like other credentials: medical licenses or elevator certificates of inspection. They were wallet-sized, of course, but they didn’t have much security associated with them. Then, slowly, driver’s licenses took on a second application: they became age-verification tokens in bars and liquor stores. Of course the security wasn’t up to the task—teenagers can be extraordinarily resourceful if they set their minds to it—and over the decades driver’s licenses got photographs, tamper-resistant features (once, it was easy to modify the birth year), and technologies that made counterfeiting harder. There was little value in counterfeiting a driver’s license, but a lot of value in counterfeiting an age-verification token.

Today, US driver’s licenses are taking on yet another function: security against terrorists. The Real ID Act—the government’s attempt to make driver’s licenses even more secure—has nothing to do with driving or even with buying alcohol, and everything to do with trying to make that piece of plastic an effective way to verify that someone is not on the terrorist watch list. Whether this is a good idea, or actually improves security, is another matter entirely.

You can see this kind of function creep everywhere. Internet security systems designed for informational Web sites are suddenly expected to provide security for banking Web sites. Security systems that are good enough to protect cheap commodities from being stolen are suddenly ineffective once the price of those commodities rises high enough. Application security systems, designed for locally owned networks, are expected to work even when the application is moved to a cloud computing environment. And cloud computing security, designed for the needs of corporations, is expected to be suitable for government applications as well—maybe even military applications.

Sometimes it’s obvious that security systems designed for one environment won’t work in another. We don’t arm our soldiers the same way we arm our policemen, and we can’t take commercial vehicles and easily turn them into ones outfitted for the military. We understand that we might need to upgrade our home security system if we suddenly come into possession of a bag of diamonds. Yet many think the same security that protects our home computers will also protect voting machines, and the same operating systems that run our businesses are suitable for military uses.

But these are all conscious decisions, and we security professionals often know better. The real problems arise when the changes happen in the background, without any conscious thought. We build a network security system that’s perfectly adequate for the threat and—like a driver’s license becoming an age-verification token—the network accrues more and more functions. But because it has already been pronounced “secure,” we can’t get any budget to re-evaluate and improve the security until after the bad guys have figured out the vulnerabilities and exploited them.

I don’t like having to play catch-up in security, but we seem doomed to keep doing so.

This essay originally appeared in the January/February 2010 issue of IEEE Security and Privacy.

Posted on February 4, 2010 at 6:35 AMView Comments

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Sidebar photo of Bruce Schneier by Joe MacInnis.