Hacker News Reader

Comment by kkjjkgjjgg | Hacker News Reader

Ever since the movie "Demolition Man", it should be obvious why biometrics are a bad idea. (Yeah I know they also can try to scan for signs of life like blood flow - still, I don't like it).

Even without the Demolition Man scenario, an even worse issue is that you can't change your biometrics in case somebody steals them. Fake fingerprints are already easy to do, other things surely can be cloned, too.

View on HN

Kids or coworkers are not going to make fake fingerprints to mess with me. What they can do is to see password or pin code while I am typing those over my shoulder. Someone on the street also won't be able to see my pin code for unlocking phone if I use fingerprint.

Those are scenarios that biometrics are handling really well.

Biometrics against sophisticated attackers is not good idea. I don't encounter in my life "sophisticated attackers" that would spend time making copy of my fingerprint.

If you are person that has risk of running into sophisticated attackers then don't use biometrics and biometrics are bad idea.

Yeah, similarly we have crap locks in doors. They are there more to make it somewhat laborious to open to door, hence signal privacy, than make it nigh impossible to break in. That's why we have bank vaults and so on when we really want to deny access.

For convenient security you want just enough complexity a bot wont automatically unlock it, for proper security something that can be even a bit unconvenient as long as it's more secure.

I agree, biometrics should probably be in the "breakable, convenient" category.

Exactly, every-day security is there to prevent random dudes. And even they can, to stay with homes, just break a window. Serious opponents, especially if they are really motivated, will be able to break into everything. The three letter agencies, and their counterparts in other countries, are obviously on the very professional and very motivated end of the spectrum.

Personally, I don't see any reason to make overly easy for any of those parties. So no biometrical data to be exchanged for some new form dogecoin.

> Kids or coworkers are not going to make fake fingerprints to mess with me.

Don't underestimate the lenghts some people will go through for a harmless prank. But you are probably correct a modern phone's fingperprint-reader is probably not fooled by an etched stick of gummibear.

Incidentally - I always wanted to have a device that you could stick your finger into, that would use a, let's say, laser to etch different fingerprints onto the tip of my finger.

>But you are probably correct a modern phone's fingperprint-reader is probably not fooled by an etched stick of gummibear

IIRC there was an attack that was able to get past the liveliness checks by putting the fingerprint replica (a thin piece of dried elmers glue) onto a real finger.

Somebody stealing your phone will likely be able to retrieve fingerprints from it? Maybe it is too much for a random thief. But what if there are "factories" for treating stolen phones, and random thieves just sell the phones to those factories? (Not saying that happens, but it seems likely to me that such things will eventually exist - down to trying to retrieve bank codes from stolen computers and phones and trying to exploit them).

A stolen phone has hashes, not scans – if memory serves, there were a couple of old Android phones which saved the images but even that was a developer’s mistake leaving logging on rather than the design.

The sensible approaches for biometrics use them to unlock strong keys which never leave the device. If implemented correctly, this is somewhat resistant to offline brute-force attacks — certainly not impossible but not economical for going after most people.

But you can "forget" your PIN, you can't forget your iris.

It could be damaged or destroyed.

I'm thinking more of cases like robbery.

Then it is even easier for the robbers to force you to unlock your phone?

That's what meant, mistyping or forgetting your PIN under stress is plausibel, but you can always face unlock or make a iris scan. You don't even need to be conscious to do it.

Yes that is also one additional point - people will pick pin like 0000 or 12345 not to forget them which makes pins in general less secure.

Some people would set their pin the same as their debit card just to remember one number instead of multiple.

That is why finger print unlocking is quite great for day to day use.

Of course it is not enough for more complex security scenarios, but as someone else mentioned lock on my doors is quite easy to pick but still it is good enough for most of people.

I put the first forget in quotes on purpose.

https://www.macrumors.com/2019/01/14/forced-biometric-unlock...

You can easier be forced to face unlock or fingerprint unlock your phone than be forced to remember your PIN

> Kids or coworkers are not going to make fake fingerprints

In truth I have seen this done to mess with people using cellotape and creativity, so I have to warn you this is not a reasonable assumption.

> Kids or coworkers are not going to make fake fingerprints to mess with me.

I know a few kids and coworkers who absolutely would, if it would get a laugh.

> Kids or coworkers are not going to make fake fingerprints to mess with me

> Biometrics against sophisticated attackers is not good idea. I don't encounter in my life "sophisticated attackers" that would spend time making copy of my fingerprint.

You don’t yet, but we’re talking about a new form of currency in this thread, not unlocking your phone to text your spouse or show your kids a youtube video.

Money is power, which will draw in sophisticated attackers who want to amass more of both.

Reply on news.ycombinator.com