October 15, 2010
by Bruce Schneier
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In this issue:
In September, The New York Times reported that President Obama will seek sweeping laws enabling law enforcement to more easily eavesdrop on the internet. Technologies are changing, the administration argues, and modern digital systems aren't as easy to monitor as traditional telephones.
The government wants to force companies to redesign their communications systems and information networks to facilitate surveillance, and to provide law enforcement with back doors that enable them to bypass any security measures.
The proposal may seem extreme, but -- unfortunately -- it's not unique. Just a few months ago, the governments of the United Arab Emirates and Saudi Arabia threatened to ban BlackBerry devices unless the company made eavesdropping easier. China has already built a massive internet surveillance system to better control its citizens.
Formerly reserved for totalitarian countries, this wholesale surveillance of citizens has moved into the democratic world as well. Governments like Sweden, Canada and the United Kingdom are debating or passing laws giving their police new powers of internet surveillance, in many cases requiring communications system providers to redesign products and services they sell. More are passing data retention laws, forcing companies to retain customer data in case they might need to be investigated later.
Obama isn't the first U.S. president to seek expanded digital eavesdropping. The 1994 CALEA law required phone companies to build ways to better facilitate FBI eavesdropping into their digital phone switches. Since 2001, the National Security Agency has built substantial eavesdropping systems within the United States.
These laws are dangerous, both for citizens of countries like China and citizens of Western democracies. Forcing companies to redesign their communications products and services to facilitate government eavesdropping reduces privacy and liberty; that's obvious. But the laws also make us less safe. Communications systems that have no inherent eavesdropping capabilities are more secure than systems with those capabilities built in.
Any surveillance system invites both criminal appropriation and government abuse. Function creep is the most obvious abuse: New police powers, enacted to fight terrorism, are already used in situations of conventional nonterrorist crime. Internet surveillance and control will be no different.
Official misuses are bad enough, but the unofficial uses are far more worrisome. An infrastructure conducive to surveillance and control invites surveillance and control, both by the people you expect and the people you don't. Any surveillance and control system must itself be secured, and we're not very good at that. Why does anyone think that only authorized law enforcement will mine collected internet data or eavesdrop on Skype and IM conversations?
These risks are not theoretical. After 9/11, the National Security Agency built a surveillance infrastructure to eavesdrop on telephone calls and e-mails within the United States. Although procedural rules stated that only non-Americans and international phone calls were to be listened to, actual practice didn't always match those rules. NSA analysts collected more data than they were authorized to and used the system to spy on wives, girlfriends and famous people like former President Bill Clinton.
The most serious known misuse of a telecommunications surveillance infrastructure took place in Greece. Between June 2004 and March 2005, someone wiretapped more than 100 cell phones belonging to members of the Greek government -- the prime minister and the ministers of defense, foreign affairs and justice -- and other prominent people. Ericsson built this wiretapping capability into Vodafone's products, but enabled it only for governments that requested it. Greece wasn't one of those governments, but some still unknown party -- a rival political group? organized crime? -- figured out how to surreptitiously turn the feature on.
Surveillance infrastructure is easy to export. Once surveillance capabilities are built into Skype or Gmail or your BlackBerry, it's easy for more totalitarian countries to demand the same access; after all, the technical work has already been done.
Western companies such as Siemens, Nokia and Secure Computing built Iran's surveillance infrastructure, and U.S. companies like L-1 Identity Solutions helped build China's electronic police state. The next generation of worldwide citizen control will be paid for by countries like the United States.
We should be embarrassed to export eavesdropping capabilities. Secure, surveillance-free systems protect the lives of people in totalitarian countries around the world. They allow people to exchange ideas even when the government wants to limit free exchange. They power citizen journalism, political movements and social change. For example, Twitter's anonymity saved the lives of Iranian dissidents -- anonymity that many governments want to eliminate.
Yes, communications technologies are used by both the good guys and the bad guys. But the good guys far outnumber the bad guys, and it's far more valuable to make sure they're secure than it is to cripple them on the off chance it might help catch a bad guy. It's like the FBI demanding that no automobiles drive above 50 mph, so they can more easily pursue getaway cars. It might or might not work -- but, regardless, the cost to society of the resulting slowdown would be enormous.
It's bad civic hygiene to build technologies that could someday be used to facilitate a police state. No matter what the eavesdroppers say, these systems cost too much and put us all at greater risk.
This essay previously appeared on CNN.com.
Eavesdropping on Bill Clinton:
Wiretapping cell phones in Greece:
Kenzero is a Japanese Trojan that collects and publishes users' porn surfing habits, and then blackmails them, requiring them to pay to have the information removed.
There's a paper at the upcoming ACM CCS conference examining similar Japanese scams.
Vulnerabilities in US-CERT network. You'd think they'd do somewhat better.
Not answering questions at U.S. Customs.
Police set up a highway sign warning motorists that there are random stops for narcotics checks ahead, but they actually search people who take the next exit. Clever real-world honeypot.
A graphical representation of popular usernames and passwords.
DHS *still* worried about terrorists using Internet surveillance.
DARPA is looking for something that can automatically declassify documents.
Good essay questioning counterterrorism policy:
This list of "Four Irrefutable Security Laws" is from Malcolm Harkins, Intel's chief information security officer: 1) users want to click on things, 2) code wants to be wrong, 3) services want to be on, and 4) security features can be used to harm.
Statistical distribution of combat wounds to the head.
I stayed clear of Haystack -- the anonymity program that was going to protect the privacy of dissidents the world over -- because I didn't have enough details about the program to have an intelligent opinion. The project has since imploded, and here are two excellent essays about the program and the hype surrounding it.
A new prepaid electricity meter fraud:
Evercookies: extremely persistent browser cookies.
In an article about Robert Woodward's new book, Obama's Wars, this is listed as one of the book's "disclosures": "A new capability developed by the National Security Agency has dramatically increased the speed at which intercepted communications can be turned around into useful information for intelligence analysts and covert operators. 'They talk, we listen. They move, we observe. Given the opportunity, we react operationally,' then-Director of National Intelligence Mike McConnell explained to Obama at a briefing two days after he was elected president." Eavesdropping is easy. Getting actual intelligence to the hands of people is hard. It sounds as if the NSA has advanced capabilities to automatically sift through massive amounts of electronic communications and find the few bits worth relaying to intelligence officers.
Serious new attack against ASP.NET:
It's better to try to isolate parts of a terrorist network than to attempt to destroy it as a whole, at least according to this model:
The cultural cognition of risk:
Stealing money from a safe with a vacuum.
This is a list of master's theses from the Naval Postgraduate School's Center for Homeland Defense and Security, this year.
Monitoring employees' online behavior: not their online behavior at work, but their online behavior in life.
I regularly say that security decisions are primarily made for non-security reasons. This article about the placement of sky marshals on airplanes is an excellent example. Basically, the airlines would prefer they fly coach instead of first class.
New research: "Attacks and Design of Image Recognition CAPTCHAs."
The politics of allocating Homeland Security money to states.
Hacking trial breaks D.C. Internet voting system. It was easy.
The ineffectiveness of vague security warnings.
Good article from The Economist on biometrics.
Remember the Mahmoud al-Mabhouh assassination last January? The police identified 30 suspects, but haven't been able to find any of them. "Police spent about 10,000 hours poring over footage from some 1,500 security cameras around Dubai. Using face-recognition software, electronic-payment records, receipts and interviews with taxi drivers and hotel staff, they put together a list of suspects and publicized it." But every trail has gone cold. Seems ubiquitous electronic surveillance is no match for a sufficiently advanced adversary.
The FBI is tracking a college student in Silicon Valley. He's 20, partially Egyptian, and studying marketing at Mission College. He found the tracking device attached to his car. Near as he could tell, what he did to warrant the FBI's attention was be the friend of someone who did something to warrant the FBI's attention.
Pen-and-paper SQL injection attack against Swedish election:
New technology that can pick a single voice out of a crowded and noisy stadium:
During the cyberwar debate a few months ago, I said this:
If we frame this discussion as a war discussion, then what you do
More of my writings on cyberwar are here:
This will help some.
At least two rival systems plan to put unique codes on packages
To defeat the system, the counterfeiter has to copy the bar codes. If the stores selling to customers are in on the scam, it can be the same code. If not, there have to be sufficient different bar codes that the store doesn't detect duplications. Presumably, numbers that are known to have been copied are added to the database, so the counterfeiters need to keep updating their codes. And presumably the codes are cryptographically hard to predict, so the only way to keep updating them is to look at legitimate products.
Another attack would be to intercept the verification system. A man-in-the-middle attack against the phone number or the website would be difficult, but presumably the verification information would be on the object itself. It would be easy to swap in a fake phone number that would verify anything.
It'll be interesting to see how the counterfeiters get around this security measure.
On October 19, I'll be giving a keynote speech at Information Security Trends Meeting 2010 in Medellin, Colombia. On October 20, I'll be giving a keynote in Bogotá, Colombia, as part of the same conference.
I'll be speaking at the GRC Meeting in Lisbon, Portugal, on October 28.
On November 6, I'll be speaking in Milton Keynes, UK, at the annual ACCU Security Fundraising Conference, in support of the Bletchley Park Trust and The National Museum of Computing.
I'll be speaking at the Gartner Symposium/ITxpo in Nice on November 8.
My musical recording debut. It's not about security.
Computer security experts are often surprised at which stories get picked up by the mainstream media. Sometimes it makes no sense. Why this particular data breach, vulnerability, or worm and not others? Sometimes it's obvious. In the case of Stuxnet, there's a great story.
As the story goes, the Stuxnet worm was designed and released by a government--the U.S. and Israel are the most common suspects--specifically to attack the Bushehr nuclear power plant in Iran. How could anyone not report that? It combines computer attacks, nuclear power, spy agencies and a country that's a pariah to much of the world. The only problem with the story is that it's almost entirely speculation.
Here's what we do know: Stuxnet is an Internet worm that infects Windows computers. It primarily spreads via USB sticks, which allows it to get into computers and networks not normally connected to the Internet. Once inside a network, it uses a variety of mechanisms to propagate to other machines within that network and gain privilege once it has infected those machines. These mechanisms include both known and patched vulnerabilities, and four "zero-day exploits": vulnerabilities that were unknown and unpatched when the worm was released. (All the infection vulnerabilities have since been patched.)
Stuxnet doesn't actually do anything on those infected Windows computers, because they're not the real target. What Stuxnet looks for is a particular model of Programmable Logic Controller (PLC) made by Siemens (the press often refers to these as SCADA systems, which is technically incorrect). These are small embedded industrial control systems that run all sorts of automated processes: on factory floors, in chemical plants, in oil refineries, at pipelines--and, yes, in nuclear power plants. These PLCs are often controlled by computers, and Stuxnet looks for Siemens SIMATIC WinCC/Step 7 controller software.
If it doesn't find one, it does nothing. If it does, it infects it using yet another unknown and unpatched vulnerability, this one in the controller software. Then it reads and changes particular bits of data in the controlled PLCs. It's impossible to predict the effects of this without knowing what the PLC is doing and how it is programmed, and that programming can be unique based on the application. But the changes are very specific, leading many to believe that Stuxnet is targeting a specific PLC, or a specific group of PLCs, performing a specific function in a specific location--and that Stuxnet's authors knew exactly what they were targeting.
It's already infected more than 50,000 Windows computers, and Siemens has reported 14 infected control systems, many in Germany. (These numbers were certainly out of date as soon as I typed them.) We don't know of any physical damage Stuxnet has caused, although there are rumors that it was responsible for the failure of India's INSAT-4B satellite in July. We believe that it did infect the Bushehr plant.
All the anti-virus programs detect and remove Stuxnet from Windows systems.
Stuxnet was first discovered in late June, although there's speculation that it was released a year earlier. As worms go, it's very complex and got more complex over time. In addition to the multiple vulnerabilities that it exploits, it installs its own driver into Windows. These have to be signed, of course, but Stuxnet used a stolen legitimate certificate. Interestingly, the stolen certificate was revoked on July 16, and a Stuxnet variant with a different stolen certificate was discovered on July 17.
Over time the attackers swapped out modules that didn't work and replaced them with new ones--perhaps as Stuxnet made its way to its intended target. Those certificates first appeared in January. USB propagation, in March.
Stuxnet has two ways to update itself. It checks back to two control servers, one in Malaysia and the other in Denmark, but also uses a peer-to-peer update system: When two Stuxnet infections encounter each other, they compare versions and make sure they both have the most recent one. It also has a kill date of June 24, 2012. On that date, the worm will stop spreading and delete itself.
We don't know who wrote Stuxnet. We don't know why. We don't know what the target is, or if Stuxnet reached it. But you can see why there is so much speculation that it was created by a government.
Stuxnet doesn't act like a criminal worm. It doesn't spread indiscriminately. It doesn't steal credit card information or account login credentials. It doesn't herd infected computers into a botnet. It uses multiple zero-day vulnerabilities. A criminal group would be smarter to create different worm variants and use one in each. Stuxnet performs sabotage. It doesn't threaten sabotage, like a criminal organization intent on extortion might.
Stuxnet was expensive to create. Estimates are that it took 8 to 10 people six months to write. There's also the lab setup--surely any organization that goes to all this trouble would test the thing before releasing it--and the intelligence gathering to know exactly how to target it. Additionally, zero-day exploits are valuable. They're hard to find, and they can only be used once. Whoever wrote Stuxnet was willing to spend a lot of money to ensure that whatever job it was intended to do would be done.
None of this points to the Bushehr nuclear power plant in Iran, though. Best I can tell, this rumor was started by Ralph Langner, a security researcher from Germany. He labeled his theory "highly speculative," and based it primarily on the facts that Iran had an unusually high number of infections (the rumor that it had the most infections of any country seems not to be true), that the Bushehr nuclear plant is a juicy target, and that some of the other countries with high infection rates--India, Indonesia, and Pakistan--are countries where the same Russian contractor involved in Bushehr is also involved. This rumor moved into the computer press and then into the mainstream press, where it became the accepted story, without any of the original caveats.
Once a theory takes hold, though, it's easy to find more evidence. The word "myrtus" appears in the worm: an artifact that the compiler left, possibly by accident. That's the myrtle plant. Of course, that doesn't mean that druids wrote Stuxnet. According to the story, it refers to Queen Esther, also known as Hadassah; she saved the Persian Jews from genocide in the 4th century B.C. "Hadassah" means "myrtle" in Hebrew.
Stuxnet also sets a registry value of "19790509" to alert new copies of Stuxnet that the computer has already been infected. It's rather obviously a date, but instead of looking at the gazillion things--large and small--that happened on that the date, the story insists it refers to the date Persian Jew Habib Elghanain was executed in Tehran for spying for Israel.
Sure, these markers could point to Israel as the author. On the other hand, Stuxnet's authors were uncommonly thorough about not leaving clues in their code; the markers could have been deliberately planted by someone who wanted to frame Israel. Or they could have been deliberately planted by Israel, who wanted us to think they were planted by someone who wanted to frame Israel. Once you start walking down this road, it's impossible to know when to stop.
Another number found in Stuxnet is 0xDEADF007. Perhaps that means "Dead Fool" or "Dead Foot," a term that refers to an airplane engine failure. Perhaps this means Stuxnet is trying to cause the targeted system to fail. Or perhaps not. Still, a targeted worm designed to cause a specific sabotage seems to be the most likely explanation.
If that's the case, why is Stuxnet so sloppily targeted? Why doesn't Stuxnet erase itself when it realizes it's not in the targeted network? When it infects a network via USB stick, it's supposed to only spread to three additional computers and to erase itself after 21 days--but it doesn't do that. A mistake in programming, or a feature in the code not enabled? Maybe we're not supposed to reverse engineer the target. By allowing Stuxnet to spread globally, its authors committed collateral damage worldwide. From a foreign policy perspective, that seems dumb. But maybe Stuxnet's authors didn't care.
My guess is that Stuxnet's authors, and its target, will forever remain a mystery.
This essay originally appeared on Forbes.com.
1. A research project that got out of control. Researchers have accidentally released worms before. But given the press, and the fact that any researcher working on something like this would be talking to friends, colleagues, and his advisor, I would expect someone to have outed him by now, especially if it was done by a team.
2. A criminal worm designed to demonstrate a capability. Sure, that's possible. Stuxnet could be a prelude to extortion. But I think a cheaper demonstration would be just as effective. Then again, maybe not.
3. A message. It's hard to speculate any further, because we don't know who the message is for, or its context. Presumably the intended recipient would know. Maybe it's a "look what we can do" message. Or an "if you don't listen to us, we'll do worse next time" message. Again, it's a very expensive message, but maybe one of the pieces of the message is "we have so many resources that we can burn four or five man-years of effort and four zero-day vulnerabilities just for the fun of it." If that message were for me, I'd be impressed.
4. A worm released by the U.S. military to scare the government into giving it more budget and power over cybersecurity. Nah, that sort of conspiracy is much more common in fiction than in real life.
Note that some of these alternate explanations overlap.
Good technical info on Stuxnet:
Since 1998, CRYPTO-GRAM has been a free monthly newsletter providing summaries, analyses, insights, and commentaries on security: computer and otherwise. You can subscribe, unsubscribe, or change your address on the Web at <http://www.schneier.com/crypto-gram.html>. Back issues are also available at that URL.
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CRYPTO-GRAM is written by Bruce Schneier. Schneier is the author of the best sellers "Schneier on Security," "Beyond Fear," "Secrets and Lies," and "Applied Cryptography," and an inventor of the Blowfish, Twofish, Threefish, Helix, Phelix, and Skein algorithms. He is the Chief Security Technology Officer of BT BCSG, and is on the Board of Directors of the Electronic Privacy Information Center (EPIC). He is a frequent writer and lecturer on security topics. See <http://www.schneier.com>.
Crypto-Gram is a personal newsletter. Opinions expressed are not necessarily those of BT.
Copyright (c) 2010 by Bruce Schneier.
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