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Securing a travel iPhone

blog.filippo.io

91–100 of 113 posts

Re: Securing a travel iPhone

#91

Earlier quoted context omitted.

I did this so I can unlock my phone with my snowboarding gloves on. I can unlock with the nose and then press the texting app button with my nose to read tests.

Do we know if nose-prints are particularly unique? Or even unique in the context of how fingerprints are typically analysed?

I did this and then tested it against several friends and family. I could only unlock the phone about 75% of the time, but I never got a false positive after about 20 different tries over the next week or two (cleaning the sensor regularly, of course)

Re: Securing a travel iPhone

#93

As someone in a country with a serious mugging problem and having lost an iPhone already, one of the biggest security flaws I see is being able to power it off without providing any authentication. What is even the point of Find my Phone and all that if anyone can just instantly switch off all the tracking?? You can't even ring your own number after that, and even law enforcement cannot look up the cell tower logs to…

Even if Apple added that, it's trivially easy to pop the SIM. A phone without a network connection won't ping, so that won't help. You have to think about it from the attacker's point of view. Anyone they sell it to is going to power it on to test it. Once it's powered on, it'll ping back. Any black-market buyer knows to pop the SIM anyway before powering it on, and turn on the phone without any publicly-accessible W…

Since it's possible to call 911/112 with a GSM phone without SIM, the phone can still be tracked throughout the network with it's unique IMEI number.

Re: Securing a travel iPhone

#94

Earlier quoted context omitted.

if I unlock my phone with a duress code or imprint my duress-coded fingerprint, reboot the phone (to look like it was a glitch-induced reboot) and present the PIN prompt again. Auto-wipe the phone if the duress code is given again this second time. If such a feature was commonplace, criminals would know about it and wouldn't be happy when they saw you activate it with your middle finger (I mean, who wouldn't use thei…

So you'd use the PIN. Then they get the metaphorical middle finger without seeing you use the real one. Besides, no criminal cares about your phone being unlocked. They just want the phone. Well, I guess there are circumstances where a criminal wants information, but if they're the ones compelling you, you have other pressing issues that go beyond protecting information from unauthorized parties. I'm talking about be…

A criminal who is motivated to steal your phone under threat if violence is motivated to have you unlock the phone and disable 'Find my Phone' or whatever the Android equivalent is. It considerably increases the resale value since the phone can then be wiped and used by a new Apple ID.

Re: Securing a travel iPhone

#95
post #86

Earlier quoted context omitted.

It's very old phones, with external antennas the power came from the same place that the power came from to say power the LED in the aftermarket NOKIA antennas that would light up when you are getting a call or a text - wireless power. The phone had enough leakage to modulate the return signal sufficiently to be detected, it would not be the same thing as tracking a phone via its normal cellular signal it would just…

I don't believe this. Those aftermarket lighty-uppy things work by sensing your phone's response burst, which is a much stronger signal, being driven by the phone's battery, and radiated from the very nearby antenna. I do believe that you can induce a signal in a powered-off phone that can be detected nearby (several feet), by virtue of the tuned antenna if nothing else. I'm skeptical of the claim that a normal arbit…

Believe what you want but at least read it through first. This isn't about powering a cell phone via wireless power and make it connect to a cell tower this is about inducing enough power into the cell phone's RF parts to make it modulate the signal sufficiently to be able to be picked up. Essentially this isn't that much different than the passive wifi or any other backscatter communication based system.

I've seen this demonstrated around 5 years ago at an Intelligence Technology seminar open to the public at the intelligence community heritage museum, it was done across the room during a demonstration which showed active and passive phone tracking techniques (they put the phones in and out of a faraday cages during the demonstration). The phone that was used in the demonstration for the "powerless" tracking was a very old Ericsson (before it became Sony Ericsson) phone from the mid to late 90's, during that demonstration we've also been told that this method of tracking became obsolete around the early 2000's. They did not elaborate exactly what ranges this work on but what they said is that the emitter and receiver were usually separated in order to accommodate operational requirements.

Re: Securing a travel iPhone

#96

Earlier quoted context omitted.

It wasn't transmitting a proper cell signal, it was transmitting something that they could detect. I would assume that you would profile phones (of a certain make and model) and based on the return signal identify them. This was used in the early days of in places where there wasn't high cellphone density to begin with.

I wonder how that passed the FCC.

I don't think this actually violates any FCC regulations given the right circumstances a can of coke can probably be induced to create enough backscatter to be trackable via RF.

Re: Securing a travel iPhone

#97
post #90
post #78

Earlier quoted context omitted.

If you expect you can reliably turn off your phone (7 seconds) before you get in a search situation, then use a full password instead of a numeric pin, then touch ID is a great balance of convenience and security. TouchID also prevents shoulder surfing of your code. It's all about the threat model.

Correct me if I'm wrong, but isn't it also possible to just use one of your fingers that you didn't register with touch ID for 5 or so consecutive unlock attempts and it will have the same effect as rebooting your phone?

There is a slight difference.

Keychain and NSFileManager have possible modes of "kSecAttrAccessibleAfterFirstUnlock" [0] and "NSFileProtectionCompleteUntilFirstUserAuthentication" [1] respectively that are (fittingly) in an open state within your app after you've unlocked the device.

[0]: https://developer.apple.com/reference/security/ksecattracces...

[1]: https://developer.apple.com/reference/foundation/nsfilemanag...

Re: Securing a travel iPhone

#98

As someone in a country with a serious mugging problem and having lost an iPhone already, one of the biggest security flaws I see is being able to power it off without providing any authentication. What is even the point of Find my Phone and all that if anyone can just instantly switch off all the tracking?? You can't even ring your own number after that, and even law enforcement cannot look up the cell tower logs to…

Even if Apple added that, it's trivially easy to pop the SIM. A phone without a network connection won't ping, so that won't help. You have to think about it from the attacker's point of view. Anyone they sell it to is going to power it on to test it. Once it's powered on, it'll ping back. Any black-market buyer knows to pop the SIM anyway before powering it on, and turn on the phone without any publicly-accessible W…

They don't need to restore or power on to check activation lock.

You go to https://www.icloud.com/activationlock/

Re: Securing a travel iPhone

#99
post #82

As someone in a country with a serious mugging problem and having lost an iPhone already, one of the biggest security flaws I see is being able to power it off without providing any authentication. What is even the point of Find my Phone and all that if anyone can just instantly switch off all the tracking?? You can't even ring your own number after that, and even law enforcement cannot look up the cell tower logs to…

> but what can be done to increase the recoverability of these expensive items? Don't buy or walk with expensive items around? Sounds like I am being snarky, but I am serious. In some cities or areas, it is not possible to have nice stuff around. Couldn't have a nice car in my old neighborhood. The old beater I had was scratched, hit and broken into multiple times. I didn't care too much, as it was already scratched…

> And since then realized that it didn't make any sense for me to buy these expensive toys if they can easily be lost, stolen, broken _if_ it causes me so much anguish when happens. So since then I've bought used, or lower end smart phones (last one is a Moto G for $170 from 3-4 years ago) so that if it gets, broken, stolen, lost I wouldn't be too upset about it, just inconvinienced some, and would just go and buy another one. Kind of like buying another pair of pants or socks.

Interesting. Different ways of managing expected frustration. Personally, I stick to highest-end phones I can afford, for the simple reason - I was once stuck for 3 years with a phone that was so crappy that it could barely lift its own OS - fire up any app, homescreen gets killed to save memory. Somebody calls you? 25% chance that you won't be able to pick it up, because the phone will hang. Try and turn on Internet on it? If you didn't turn off sync, you'll have to powercycle the phone by removing its battery to get it working again.

I don't break or lose phones often (in the last 3 years, I managed to crack the screen of my S4 two times; got the glass replaced both times for relatively little cost). But I use them quite a lot, every day. Minor frustrations like apps crashing, hanging, or taking 30 seconds to load tend to add up into quite a bit of frustration daily. So I prefer to save up and buy a phone that I know will work flawlessly for the next 3 years or so (and, like with S4, then I happily give it away to someone when I buy a new one; they can probably squeeze 3 more years off it too).

Re: Securing a travel iPhone

#100

Hey, author here. Happy to answer questions. There's also a big Twitter thread here https://twitter.com/FiloSottile/status/750273921568485377 To frame the post and the conversation, I am targeting a loose but not universal threat model. If threat of deadly force is higher up in your risk scale than shoulder-surfing, or Apple cooperation is a given, then you might want to make very different choices, but more importan…

Just a heads up security questions can be reset with a call to AppleCare.

That's why this https://support.apple.com/en-us/KM205083?cid=acs::applesearc... article states to contact them.

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