The Google Chrome Security team begs to differ [1]. According to them giving someone the illusion of security is bad.
An understanding of security will reveal that security is not a binary state of affairs. It's perfectly reasonable to trust known-imperfect mechanisms like the iPhone fingerprint reader to keep honest people honest and discourage ordinary muggers and thieves. I don't need military-grade access control for my personal iPhone, I don't want the inconvenience that would necessarily accompany it, and I damned sure don't want to pay for it.
And the Google Chrome guy is correct in all respects: it's not reasonable to expect an application to provide security that's redundant with security provided by user accounts on the OS it runs on. It would be better to teach users to create separate accounts on their system, if they want to hide their local passwords from other members of their family.
It is perfectly reasonable to expect an application to provide more security than the user account provides because in the real world, we know that people don't always lock their computers. Not all applications are risky, but one that centralizes a users credentials is clearly so.
Pretending otherwise is simply not acknowledging the real world.
Name one security technology that is 100% foolproof. They don't exist. So the point isn't to rely on one thing, but to rely on many things that, used in concert, increase the risk, complexity and cost associated with subverting the entire system--not its individual components.
In the same way that you'd afford extra scrutiny to a government agent making claims about what encryption methods to use, you should afford the same scrutiny to companies making security claims who are documented collaborators with the TLAs.
An ad hominem isn't always a fallacy, especially when the credibility of the speaker is legitimately in question. Saying they're automatically wrong would be fallacious (not to mention silly), but questioning credibility based on actual, documented behavior is not.
The main argument is in the second paragraph.
Anyhow, thanks for noticing :)
Security is not binary.
Correct me if I'm wrong, but the biometric data never leaves the device.
You need the fingerprints themselves to fake out the hardware.
For example, the obvious approach is to store fingerprint features, which will be then matched by any print that has the same features in the same positions. If you do a good enough job of generating the new print you might even be able to fool police investigations, since they compare prints the same way.
http://lukenotricks.blogspot.com/2009/04/on-entropy-of-finge...
All bets are off with physical access to the hardware, of course.
I am not a lawyer but it seems to me, 9 times out 10, the cop would prefer a cleaner result - they confiscate your device, and oops, when you get it back, the video is gone.
...the people closest to you in your environment ( kids, parents, spouse, boss, co-workers) are the ones who can most easily obtain your fingerprints...
Also, if a fingerprint sensor is significantly easier to use, and in practice will deter a class of privacy violations, it could increase overall security. This is a question you can only answer by looking how people behave, not solely with an analysis of the technology.
The fingerprint sensor worries me more that it records biometric information at all. It's one thing to leave fingerprints all around your environment, but there is now the potential to steal your biometrics over the internet. The device supposedly hashes the data derived from your fingerprint, presumably with a hardware-based secret, but I worry someone will find a way around that. (EDIT: maybe this is physically impossible; can someone provide details?)
Also, the issues that CCC discusses about how fingerprint unlocking can be coerced are important. Many law enforcement organizations now have devices that can scan smartphone data, which is bad enough, but at least the use of those devices are controlled. A fingerprint sensor now allows a cop to handcuff someone, jam his or her finger onto the phone, and then to (for instance) delete an incriminating video.
Likewise anyone else willing to use force. Might become the next schoolyard amusement for bullies, if your kid has a smartphone.