Holy Hash!

Security is quality under attack. Hard-won lessons in software security, from someone who built the programs and wrote the standards.

Archive for the ‘technology’ tags

10 August 2012

NFC, ain’t that funny

N-Mark Logo for certified devices

When we invented NFC (Near Field Communication) we never intended it for some of the uses that it was put to afterwards. And when we started discussing those unconventional (for us) uses, we immediately pointed out all security problems and proposed methods to protect the NFC devices from various attacks. That was… probably 2004. Do you think anyone listened? Nope. After that, we put in a few years worth of work into some (ok, granted, fairly fuzzy for political reasons) guidance, standards and white papers in Ecma International and NFC Forum. Did anyone take notice? I don’t think so.

At the recent Black Hat security conference security researcher Charlie Miller detailed and demonstrated attacks to the NFC devices and showed how he can pown a mobile phone through a combination of NFC and browser attacks.

The reason? NFC is a new attack surface and it has to be protected, both by itself and in comnbination with all the other things that are operating in the same device. However, the usual thing has happened. People paid attention only to the hype of usefulness and ease of use of the technology but never paid attention to the security of it. Now the security will have to be added, again, as an afterthought.

Duh, the humanity.

20 July 2012

Biometrics – any good?

I think I already talked about this subject previously but not here. Anyhow, the subject bears repeating.

Many go “yippee!” at the mention of biometrics and start to think their user authentication problem is solved. Do not pay attention, they will end up in the newspaper headlines fairly soon, either for massive security failures or being bankrupt, or both.

Cartoon of a man being checked on biometric fe...

The problem is not a huge false negative rate, and it is not the huge false positive rate either. The problem is immutability of the characteristics. The biometric characteristics change slowly over time as you age and can be influenced by the environment but they cannot be changed at will (well, at least not easily). The problem is that whatever this thing is, it is a part of your body and is most of the time something you do not want to change even if you had a possibility to do so.

And that’s also why it is dangerous – you may end up losing a limb or two.

The first question that should be asked then, “what’s it good for, anyway?” A characteristic that is fairly stable, cannot easily be changed at will, – that’s a fairly reasonable user name, i.e. the user identification. Even then, it is a questionable approach because it is a good idea to let users change names.

Biometrics is definitely not any good for authentication, that is, proving that you are who you say you are. If you compare to the familiar authentication with passwords, you will notice that the means of authentication are supposedly:

  • secret or concealable
  • non-degradable
  • easily changeable in a controlled manner
  • transferrable in a controlled manner

And biometrics is none of that.

But why then? Oh, I do not expect to find a definitive answer to that but one thing could be that it looks cool in movies. The other is that biometrics were historically good for tracking people that are not actively resisting such tracking. But then we talk about politics and power and that is not the subject of this discussion at all. One thing is certain: whatever the reason to use biometrics is, it has absolutely nothing to do with security.

So when you see claims like “Biometric is the most secure and convenient authentication tool”, now you know that’s just utter nonsense and you should stay away from people (and companies) making such claims. Unless there isn’t enough nonsense in your life, of course.

When it’s your responsibility to implement a security system, try to stay away from biometrics, you’ll live a happier life. Leave it to Hollywood.