Schneier on Security
A blog covering security and security technology.
September 2005 Archives
A fan's view of the extra "security" at football games.
It's in a gaming world, but it's still fascinating.
Method for geolocating logical network addresses
The entire suite of cryptographic algorithms is intended to protect both classified and unclassified national security systems and information. Because Suite B is a also subset of the cryptographic algorithms approved by the National Institute of Standards, Suite B is also suitable for use throughout government. NSA's goal in presenting Suite B is to provide industry with a common set of cryptographic algorithms that they can use to create products that meet the needs of the widest range of US Government (USG) needs.
Elliptic Curve Cryptography provides greater security and more efficient performance than the first generation public key techniques (RSA and Diffie-Hellman) now in use. As vendors look to upgrade their systems they should seriously consider the elliptic curve alternative for the computational and bandwidth advantages they offer at comparable security.
At Labour's Brighton conference in the UK, security screeners are making people take their watches off and run them through the scanner. Why? No one seems to know.
My guess is that it began as this story about altimeter watches, and then got exaggerated in the retelling.
It captures criminals:
Today, even murderers carry cell phones.
I am fine with the police using this tool, as long as the warrant process is there to ensure that they don't abuse the tool.
The German government want to jam aircraft navigation equipment near nuclear power plants.
This certainly could help if terrorists want to fly an airplane into a nuclear power plant, but it feels like a movie-plot threat to me. On the other hand, this could make things significantly worse if an airplane flies near the nuclear power plant by accident. My guess is that the latter happens far more often than the former.
The Minister of the Interior of Bavaria requested that the industry produces web content filtering on "instructions on how to build a bomb." These pages, he claims, are "a very dangerous security problem." He hopes filters like those for parental filtering can solve this problem.
I think he's trying to solve the wrong problem.
It's been far too long since I've had one of these.
CryptIt looks like just another one-time pad snake-oil product:
Most file encryptions use methods that mathematically hash a password to a much larger number and rely on the time taken to reverse this process to prevent unauthorised decryption. Providing the key length is 128 bits or greater this method works well for most purposes, but since these methods do have predictable patterns they can be cracked. CPUs are increasing in speed at a fast rate and these encryption methods can be beaten given luck and/or enough computers. XorIt uses the XOR encryption method (also known as Vernam encryption) that can have keys the same size as the file to be encrypted. Thus, if you are encrypting a 5MB file, then you can have what is in effect a 40 Million bit key! This is virtually unbreakable by any computer, especially when you consider that the file must also be checked with each combination to see if it is decrypted. To put is another way, since XorIt gives no pass/fail results brute force methods are difficult to implement. In fact, if you use a good key file that is the same size or larger than the source and do not reuse the key file then it it impossible to decrypt the file, no matter how fast the computer is. Furthermore, the key file can be anything - a program, a swap file, an image of your cat or even a music file.
An article on "the Armani of bulletproof clothing."
Starting next month, US-CERT will start issuing uniform names for worms, viruses, and other malware. This is part of a program called the Common Malware Enumeration Initiative, and is great news.
From the Washington Post:
Suspects arrested or detained by federal authorities could be forced to provide samples of their DNA that would be recorded in a central database under a provision of a Senate bill to expand government collection of personal data.
Both Subway and Cold Stone Creamery have discontinued their frequent-purchaser programs because the paper documentation is too easy to forge. (The article says that forged Subway stamps are for sale on eBay.)
It used to be that the difficulty of counterfeiting paper was enough security for these sorts of low-value applications. Now that desktop publishing and printing is common, it's not. Subway is implementing a system based on magnetic stripe cards instead. Anyone care to guess how long before that's hacked?
So much for high-tech security:
Prison officers have been forced to abandon a new security system and return to the use of keys after the cutting-edge technology repeatedly failed.
Unfortunately, the article doesn't say how the prisoners hacked the system. Perhaps they lifed fingerprints off readers with transparent tape. Or perhaps the valid latent fingerprints left on the readers by wardens could be activated somehow.
I would really like some more details here. Does it really make sense to have a tokenless access system in a prison? I don't know enough to answer that question.
In this disturbing story, a man is arrested in the London subways as a terrorist because, well because he was acting like a computer nerd.
At least the police didn't shoot to kill.
EDITED TO ADD: This picture was supposedly taken in the London Tube a few weeks after the first set of bombings.
EDITED TO ADD: Snopes says that the picture is a fake.
The TSA is not going to use commercial databases in its initial roll-out of Secure Flight, its airline screening program that matches passengers with names on the Watch List and No-Fly List. I don't believe for a minute that they're shelving plans to use commercial data permanently, but at least they're delaying the process.
In other news, the report (also available here, here, and here) of the Secure Flight Privacy/IT Working Group is public. I was a member of that group, but honestly, I didn't do any writing for the report. I had given up on the process, sick of not being able to get any answers out of TSA, and believed that the report would end up in somebody's desk drawer, never to be seen again. I was stunned when I learned that the ASAC made the report public.
There's a lot of stuff in the report, but I'd like to quote the section that outlines the basic questions that the TSA was unable to answer:
The SFWG found that TSA has failed to answer certain key questions about Secure Flight: First and foremost, TSA has not articulated what the specific goals of Secure Flight are. Based on the limited test results presented to us, we cannot assess whether even the general goal of evaluating passengers for the risk they represent to aviation security is a realistic or feasible one or how TSA proposes to achieve it. We do not know how much or what kind of personal information the system will collect or how data from various sources will flow through the system.
The members of the working group, and the signatories to the report, are Martin Abrams, Linda Ackerman, James Dempsey, Edward Felten, Daniel Gallington, Lauren Gelman, Steven Lilenthal, Anna Slomovic, and myself.
And in case you think things have gotten better, there's a new story about how the no-fly list cost a pilot his job:
Cape Air pilot Robert Gray said he feels like he's living a nightmare. Two months after he sued the federal government for refusing to let him take flight training courses so he could fly larger planes, he said yesterday, his situation has only worsened.
Remember what the no-fly list is. It's a list of people who are so dangerous that they can't be allowed to board an airplane under any circumstances, yet so innocent that they can't be arrested -- even under the provisions of the PATRIOT Act.
EDITED TO ADD: The U.S. Department of Justice Inspector General released a report last month on Secure Flight, basically concluding that the costs were out of control, and that the TSA didn't know how much the program would cost in the future.
EDITED TO ADD: EPIC has received a bunch of documents about continued problems with false positives.
Here's a story (quote is from the second page) where airline security is actually doing harm:
Long lines and chaos snarled evacuees when they tried to catch flights out from two of Houston's airports. After about 100 federal security screeners failed to report to work Thursday, scores of passengers missed flights and waited for hours at sparsely monitored X-ray machines and luggage conveyors. Transportation Security Administration officials were at a loss for an explanation and scrambled to send in a team of replacement workers from Cleveland.
This isn't an easy call, but sometimes the smartest thing to do in an emergency is to suspend security rules. Unfortunately, sometimes the bad guys count on that.
If I were in charge, I would have let people onto the airplanes. The trade-off makes sense to me.
We all know that Google can be used to find all sorts of sensitive data, but here's a new twist on that:
A Spanish astronomer has admitted he accessed internet telescope logs of another astronomer's observations of a giant object orbiting beyond Neptune but denies doing anything wrong.
This seems like a really bad idea.
Stepping up the battle against entertainment piracy, Verizon Communications Co. have entered a long-term programming deal that calls for the phone company to send a warning to Internet users suspected of pirating Disney's content on its broadband services.
EDITED TO ADD: If you can't read the Wall Street Journal link, another article.
My second essay for Wired was published today. It's about the future privacy rulings of the Supreme Court:
Recent advances in technology have already had profound privacy implications, and there's every reason to believe that this trend will continue into the foreseeable future. Roberts is 50 years old. If confirmed, he could be chief justice for the next 30 years. That's a lot of future.
More movie-plot threats at the Department of Homeland Security: "How Terrorists Might Exploit a Hurricane."
Score one for security cameras:
Newly released CCTV footage shows the 7 July London bombers staged a practice run nine days before the attack.
See also The New York Times.
This scam was uncovered in Israel:
People in this country freak out at the slightest little thing.
Is a ferry that transports 3000 cars a day (during the busy season) a national security risk?
Thousands of motorists who use the Jamestown-Scotland Ferry can expect more stringent screenings this week, when the state adds armed guards and thorough car searches.
More info here
New, increased security measures are coming to the Jamestown-Scotland Ferry. Beginning July 1, security guards at the ferry will conduct random screening of passengers and their vehicles in an effort to prevent dangerous substances and devices from boarding the ferry. Commuters should prepare for a possible increase in the amount of time it takes to board the ferry once the screenings are in place; however, the ferries will depart on time according to schedule.
How many ferries like this are in the U.S.? How many other potential targets of the same magnitude are there in the U.S.? How much would it cost to secure them all?
This just isn't the way to go about it.
The ID solves a problem that doesn't exist.
Yes, it's sensationalist. But there's some good information here.
The Next 50 Years of Computer Security: An Interview with Alan Cox.
He says a lot of the same things I've been saying.
Hundreds of cases involving breath-alcohol tests have been thrown out by Seminole County judges in the past five months because the test's manufacturer will not disclose how the machines work.
I think this is huge. (Think of the implications for voting systems, for one.) And it's the right decision. Throughout history, the government has had to make the choice: prosecute, or keep your investigative methods secret. They couldn't have both. If they wanted to keep their methods secret, they had to give up on prosecution.
People have the right to confront their accuser. And people have the right to a public trial. This is the correct decision, and we are all safer because of it.
I very am interested in this kind of research:
Network Structure, Behavioral Considerations and Risk Management in Interdependent Security Games
Interesting law-review article on crime-facilitating speech.
From the Mitsuibshi Research Laboratories:
The privacy-enhanced computer display uses a ferroelectric shutter glasses and a special device driver to produce a computer display which can be read only by the desired recipient, and not by an onlooker. The display alternately displays the desired information in one field, then the inverse image of the desired information in the next field, at up to 120 Hz refresh. The ferroelectric shutter glasses allow only the desired information to be viewed, while the inverse image causes unauthorized viewers to perceive only a flickering gray image, caused by the persistence of vision in the human visual system. It is also possible to use the system to "underlay" a private message on a public display system.
Fascinating research out of Berkeley. Ed Felten has a good summary:
Li Zhuang, Feng Zhou, and Doug Tygar have an interesting new paper showing that if you have an audio recording of somebody typing on an ordinary computer keyboard for fifteen minutes or so, you can figure out everything they typed. The idea is that different keys tend to make slightly different sounds, and although you don't know in advance which keys make which sounds, you can use machine learning to figure that out, assuming that the person is mostly typing English text. (Presumably it would work for other languages too.)
Read the rest.
The paper is on the Web. Here's the abstract:
We examine the problem of keyboard acoustic emanations. We present a novel attack taking as input a 10-minute sound recording of a user typing English text using a keyboard, and then recovering up to 96% of typed characters. There is no need for a labeled training recording. Moreover the recognizer bootstrapped this way can even recognize random text such as passwords: In our experiments, 90% of 5-character random passwords using only letters can be generated in fewer than 20 attempts by an adversary; 80% of 10-character passwords can be generated in fewer than 75 attempts. Our attack uses the statistical constraints of the underlying content, English language, to reconstruct text from sound recordings without any labeled training data. The attack uses a combination of standard machine learning and speech recognition techniques, including cepstrum features, Hidden Markov Models, linear classification, and feedback-based incremental learning.
Putting aside geopolitics for a minute (whether I call it a "wall" or a "fence" is a political decision, for example), it's interesting to read the technical security details about the barrier the Israelis built around Gaza:
Remote control machine guns, robotic jeeps, a double fence, ditches and pillboxes along with digitally-linked commanders are all part of the IDF's new 60-kilometer layered protection around the Gaza Strip.
In Beyond Fear pages 207-8, I wrote about the technical details of the Berlin Wall. This is far more sophisticated.
I had an op ed published in the Minneapolis Star-Tribune today.
Toward a Truly Safer Nation
Leaving aside the political posturing and the finger-pointing, how did our nation mishandle Katrina so badly? After spending tens of billions of dollars on homeland security (hundreds of billions, if you include the war in Iraq) in the four years after 9/11, what did we do wrong? Why were there so many failures at the local, state and federal levels?
These are reasonable questions. Katrina was a natural disaster and not a terrorist attack, but that only matters before the event. Large-scale terrorist attacks and natural disasters differ in cause, but they're very similar in aftermath. And one can easily imagine a Katrina-like aftermath to a terrorist attack, especially one involving nuclear, biological or chemical weapons.
Improving our disaster response was discussed in the months after 9/11. We were going to give money to local governments to fund first responders. We established the Department of Homeland Security to streamline the chains of command and facilitate efficient and effective response.
The problem is that we all got caught up in "movie-plot threats," specific attack scenarios that capture the imagination and then the dollars. Whether it's terrorists with box cutters or bombs in their shoes, we fear what we can imagine. We're searching backpacks in the subways of New York, because this year's movie plot is based on a terrorist bombing in the London subways.
Funding security based on movie plots looks good on television, and gets people reelected. But there are millions of possible scenarios, and we're going to guess wrong. The billions spent defending airlines are wasted if the terrorists bomb crowded shopping malls instead.
Our nation needs to spend its homeland security dollars on two things: intelligence-gathering and emergency response. These two things will help us regardless of what the terrorists are plotting, and the second helps both against terrorist attacks and national disasters.
Katrina demonstrated that we haven't invested enough in emergency response. New Orleans police officers couldn't talk with each other after power outages shut down their primary communications system -- and there was no backup. The Department of Homeland Security, which was established in order to centralize federal response in a situation like this, couldn't figure out who was in charge or what to do, and actively obstructed aid by others. FEMA did no better, and thousands died while turf battles were being fought.
Our government's ineptitude in the aftermath of Katrina demonstrates how little we're getting for all our security spending. It's unconscionable that we're wasting our money fingerprinting foreigners, profiling airline passengers, and invading foreign countries while emergency response at home goes underfunded.
Money spent on emergency response makes us safer, regardless of what the next disaster is, whether terrorist-made or natural.
This includes good communications on the ground, good coordination up the command chain, and resources -- people and supplies -- that can be quickly deployed wherever they're needed.
Similarly, money spent on intelligence-gathering makes us safer, regardless of what the next disaster is. Against terrorism, that includes the NSA and the CIA. Against natural disasters, that includes the National Weather Service and the National Earthquake Information Center.
Katrina deftly illustrated homeland security's biggest challenge: guessing correctly. The solution is to fund security that doesn't rely on guessing. Defending against movie plots doesn't make us appreciably safer. Emergency response does. It lessens the damage and suffering caused by disasters, whether man-made, like 9/11, or nature-made, like Katrina.
I don't always agree with everything Marcus says, but he's always interesting and entertaining and thought provoking. This is his latest essay: "The Six Dumbest Ideas in Computer Security."
Criminals are adapting to advances in forensic science:
There is an increasing trend for criminals to use plastic gloves during break-ins and condoms during rapes to avoid leaving their DNA at the scene. Dostie describes a murder case in which the assailant tried to wash away his DNA using shampoo. Police in Manchester in the UK say that car thieves there have started to dump cigarette butts from bins in stolen cars before they abandon them. "Suddenly the police have 20 potential people in the car," says Rutty.
The article also talks about forensic-science television shows changing the expectations of jurors.
"Jurors who watch CSI believe that those scenarios, where forensic scientists are always right, are what really happens," says Peter Bull, a forensic sedimentologist at the University of Oxford. It means that in court, juries are not impressed with evidence presented in cautious scientific terms.
Fascinating article on A.G. Tolkachev, a Russian who spied for the CIA for almost ten years. I was particularly interested in reading the tradecraft descriptions.
Note that the article was published in the CIA journal Studies in Intelligence, and is unclassified.
Wired.com just published an essay by me: "Terrorists Don't Do Movie Plots."
Sometimes it seems like the people in charge of homeland security spend too much time watching action movies. They defend against specific movie plots instead of against the broad threats of terrorism.
I'm now doing a bi-weekly column for them. I will post a link to the essays when they appear on the Wired.com site, and will reprint them in the next Crypto-Gram.
This seems like a really bad idea:
Government has the right -- even the responsibility -- to see that its laws and regulations are enforced. The Internet is no exception. When the Internet is being used on American soil, it should comply with American law. And if it doesn't, then the government should be able to step in and filter the illegal sites and activities.
Here's a criminal who "stole" keys, the physical metal ones, by examining images of them being used:
He surreptitiously videotaped letter carriers as they opened the boxes, zooming in on their keys. Lau used those images to calculate measurements for the grooves in the keys and created brass duplicates.
Technology causes security imbalances. Sometimes those imbalances favor the defender, and sometimes they favor the attacker. What we have here is a new application of a technology by an attacker.
Lance Armstrong has been accused of using a banned substance while racing the Tour de France. From a security perspective, this isn't very interesting. Blood and urine tests are used to detect banned substances all the time. But what is interesting is that the urine sample was from 1999, and the test was done in 2005.
Back in 1999, there was no test for the drug EPO. Now there is. Someone took a old usine sample -- who knew that they stored old urine samples? -- and ran the new test.
This ability of a security mechanism to go back in time is interesting, and similar to police exhuming dead bodies for new forensic analysis, or a new cryptographic technique permitting decades-old encrypted messages to be read.
It also has some serious ramifications for athletes considering using banned substances. Not only do they have to evade any tests that exist today, but they have to at least think about how they could evade any tests that might be invented in the future. You could easily imagine athletes being stripped of their records, medals, and titles decades in the future after past transgressions are discovered.
On the other hand, athletes accused of using banned substances in the past have limited means by which to defend themselves. Perhaps they will start storing samples of their own blood and urine in escrow, year after year, so they'd have well-stored and untainted bodily fluids with which to refute charges of past transgressions.
Emily Finch, of the University of East Anglia, has researched criminals and how they adapt their fraud techniques to identity cards, especially the "chip and PIN" system that is currently being adapted in the UK. Her analysis: the security measures don't help:
"There are various strategies that fraudsters use to get around the pin problem," she said. "One of the things that is very clear is that it is a difficult matter for a fraudster to get hold of somebody's card and then find out the pin.
Reliance in the technology actually reduces security, because people stop paying attention:
"One of the things we found quite alarming was how much the human element has been taken out of point-of-sale transactions," Dr Finch said. "Point-of-sale staff are told to look away when people put their pin number in; so they don't check at all."
I've been saying this kind of thing for a while, and it's nice to read about some research that backs it up.
There are many, large and small, but I want to mention two that I haven't seen discussed elsewhere.
1. The aftermath of this tragedy reflects on how poorly we've been spending our homeland security dollars. Again and again, I've said that we need to invest in 1) intelligence gathering, and 2) emergency response. These two things will help us regardless of what the terrorists are plotting, and the second helps in the event of a natural disaster. (In general, the only difference between a manmade disaster and a natural one is the cause. After a disaster occurs, it doesn't matter.) The response by DHS and FEMA was abysmal, and demonstrated how little we've been getting for all our security spending. It's unconscionable that we're wasting our money on national ID cards, airline passenger profiling, and foreign invasions rather than emergency response at home: communications, training, transportation, coordination.
2. Redundancy, and to a lesser extent, inefficiency, are good for security. Efficiency is brittle. Redundancy results in less-brittle systems, and provides defense in depth. We need multiple organizations with overlapping capabilities, all helping in their own way: FEMA, DHS, the military, the Red Cross, etc. We need overcapacity, in water pumping capabilities, communications, emergency supplies, and so on. I wrote about this back in 2001, in opposition to the formation of the Department of Homeland Security. The government's response to Katrina demonstrates this yet again.
"The Digital-ER mailing list is dedicated to dicussing technical solutions to emergency and crisis management."
A fun story about a bad game-show random-number generator.
From Karl Lembke:
In the latest Harry Potter book, we see Hogwarts implementing security precautions in order to safeguard its students and faculty.
And while we're on the subject, can you really render a powerful wizard helpless simply by taking away his wand? And is taking away a powerful wizard's wand simply as easy as doing something to him at the same time he is doing something else?
One, this means that you're dead if you're outnumbered. All it would take it two synchronized wizards, both of much lower power level, to defeat a powerful wizard. And two, it means that you're dead if you're taking by surprise or distracted.
This seems like an enormous hole in magical defenses, one that wizards would have worked feverishly to close up generations ago.
EDITED TO ADD: Here's a page on trust in the series.
Global secrets are generally considered poor security. The problems are twofold. One, you cannot apply any granularity to the security system; someone either knows the secret or does not. And two, global secrets are brittle. They fail badly; if the secret gets out, then the bad guys have a pretty powerful secret.
This is the situation right now in Sydney, where someone stole the master key that gives access to every train in the metropolitan area, and also starts them.
Unfortunately, this isn't a thief who got lucky. It happened twice, and it's possible that the keys were the target:
The keys, each of which could start every train, were taken in separate robberies within hours of each other from the North Shore Line although police believed the thefts were unrelated, a RailCorp spokeswoman said.
So, what can someone do with the master key to the Sydney subway? It's more likely a criminal than a terrorist, but even so it's definitely a serious issue:
A spokesman for RailCorp told the paper it was taking the matter "very seriously," but would not change the locks on its trains.
I don't know if RailCorp should change the locks. I don't know the risk: whether that "range of security measures" only protects against train theft -- an unlikely scenario, if you ask me -- or other potential scenarios as well. And I don't know how expensive it would be to change the locks.
Another problem with global secrets is that it's expensive to recover from a security failure.
And this certainly isn't the first time a master key fell into the wrong hands:
Mr Graham said there was no point changing any of the metropolitan railway key locks.
A final problem with global secrets is that it's simply too easy to lose control of them.
Moral: Don't rely on global secrets.
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