TaoSecurity Blog

If you've been following the last few days of posts, I've been thinking about security from a more general level. I've been wondering how we can mitigate risks in a digital world where the following features are appearing in nearly every digital device. Think about digital devices in your possession and see if you agree with this characterization of their development. Digital devices are increasingly: Autonomous: This means they act on their own, often without user confirmation. They are self-updating (downloading patches, firmware) and self-configuring (think zeroconf in IPv6). Users could potentially alter this behavior, but probably not without breaking functionality. Powerful: A cell phone is becoming as robust as a laptop. Almost any platform will be able to offer a shell to those who can solicit it . There is no way to prevent this development -- and would we really want to? Ubiquitous: Embedded devices are everywhere. You cannot buy a car without one. I ex...

If you were to pass the dark alley in the image at left, I doubt you would want to enter it. You could imagine all sorts of nasty encounters that might deprive you of property, limb, or life. Yet, few people can imagine the sorts of danger they encounter when using a public PC terminal, or connecting to a wireless access point, or visiting a malicious Web site with a vulnerable browser. This is the problem with envisaging risk that I discussed earlier this week. Furthermore, security in the analog world is much threat-centric. If I'm walking near or in a dark alley, and I see a shady character, I sense risk. I don't walk down the street checking myself for vulnerabilities, ignoring the threats watching me. ("Exposed neck? Could get hurt there. Bare hands? Might get burnt by acid." Etc...) It seems like the digital security model is like an unarmed combatant in a war zone. Survivability is determined solely by vulnerability exposure, the attractiveness of ...

So-called intrusion prevention systems (IPS) are all the rage. Since the 2003 Gartner report declaring intrusion detection systems (IDS) dead, the IPS has been seen as the "natural evolution" of IDS technology. If you can detect an attack, goes a popular line of reasoning, why can't (or shouldn't) you stop it? Here are a few thoughts on this issue. People who make this argument assume that prevention is an activity with zero cost or down side. The reality is that the prevention action might just as easily stop legitimate traffic. Someone has to decide what level of interruption is acceptible. For many enterprises -- especially those where interruption equals lost revenue -- IPS is a non-starter. (Shoot, I've dealt with companies that tolerated known intrusions for years because they didn't want to "impact" the network!) If you're not allowed to interrupt traffic, what is the remaining course of action? The answer is inspection, followed ...

As I continue through my list of security notes, I thought I would share a few ideas here. I recorded these while seeing Ron Gula discuss vulnerability management at RMISC . Many people recommend automated patching, at least for desktops. In the enterprise, some people believe patches should be tested prior to rollout. This sounds like automated patching must be disabled. I'm wondering if anyoen has implemented delayed automated patching . In other words, automatic updates are enabled, but with a two or three day delay. Those two or three days give the enterprise security group time to test the patch. If everything is ok, they let the automated patch proceed. If the patch breaks something critical, they instruct the desktops to not install the patch until further orders. I think this approach strikes a good balance since I would prefer to have automated patch installation be the default tactic, not manual installation. Determining which systems are vulnerable results in im...

Just today I mentioned that there is no such thing as return on security investment (ROSI). I was saying this two years ago . As I was reviewing my notes, I remembered one true case of ROSI: the film Road House . If you've never seen it, you're in for a treat. It's amazing that this masterpiece is only separated by four years from Swayze's other classic, Red Dawn . (Best quote from Red Dawn: A member of an elite paramilitary organization: "Eagle Scouts." ) In Road House, Swayze plays a "cooler" -- a bouncer who cleans up unruly bars. He's hired to remove the riff raff from the "Double Deuce," a bar so rough the band is protected by a chicken wire fence! I personally would have hired Jackie Chan, but that's a story for another day. Swayze's character indeed fights his way through a variety of local toughs, in the process allowing classier and richer patrons to frequent the Double Deuce. The owner clearly sees a ROSI; the...

One of my favorite aspects of attending USENIX conferences is receiving free copies of magazines like IEEE Security and Privacy . The March/April 2005 issue (ok, I'm way behind when I use the freebie method) features two articles that might be interesting to security folks. First, if you want a good summary of trusted computing, read Protecting Client Privacy with Trusted Computing at the Server (.pdf). To get insights on the differences between computer science and computer engineering, try Turing is from Mars, Shannon in from Venus (.pdf). Since Dartmouth faculty wrote both articles, they're published free through dartmouth.edu.

I've written about Common Critera before. If you also think CC is a waste of money, read GAO: Common Criteria Is Not Common Enough by Michael Arnone. It summarizes and comments upon a report by the Government Accounting Office titled INFORMATION ASSURANCE: National Partnership Offers Benefits, but Faces Considerable Challenges . Mr. Arnone writes: GAO also criticized the National Information Assurance Partnership (NIAP) for not providing metrics or evidence that the Common Criteria actually improves product security. In addition, the Common Criteria process takes so long to complete that agencies often find that the products they need are not on the list of certified offerings or that only older versions have been accredited, GAO’s report states... Pescatore said GAO’s call for increased education and awareness of NIAP’s function is overblown. Large vendors already know the process well and can afford millions of dollars for tailor-made product evaluations, he said. Any edu...