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FBI is warning people against using public phone-charging stations

schneier.com

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Re: FBI is warning people against using public phone-charging stations

#261

Post by amluto »

moritonal wrote: post #14
RcouF1uZ4gsC wrote: post #9

This might be a big advantage for wireless charging. Although it can be slower than a USB charger, there is no risk that it will be doing something other than charging.

Firstly, I believe the QI scheme includes a process for communication, mostly restricted to "how much power should I send" for now, but it's obvious this will be expanded to more functionality as people basically replicate NFC over it. Second, I'm still waiting to see a QI charger than just pumps 100W of power straight through any piece of metal above it. Don't know what would happen, but I naively imagine forced ind…

As I understand it, Qi has a digital communication channel from the phone to the charger but no digital communication from charger to phone. So any exploit over Qi would have to somehow compromise the phone’s charging system with just analog field variations (frequency, field strength, or whatever else the phone measures).

Re: FBI is warning people against using public phone-charging stations

#262

Post by detrites »

rsync wrote: post #251
TheNewsIsHere wrote: post #195

Earlier quoted context omitted.

I try to always travel with a “USB data condom”. The one I have is called a “PortaPow”, and it’s red. It was about $10 on Amazon and it’s a great investment for scenarios where I _reasonably_ trust a power-only USB port not to have been tampered with, like the built in ports on aircraft.

I have long used usb condoms - even on my own, trusted ports. Sometimes I just want to charge my phone from my laptop without triggering all kinds of finder and iTunes and photos interactions. Same with a car - just power, please.

Build condoms into the devices themselves via a next USB spec requiring a hardware switch to choose power-only / power+data and these kind of issues could disappear. Apple might hate it though. Then again, capacitive hardware switches could be ok.

Re: FBI is warning people against using public phone-charging stations

#263

Post by maerF0x0 »

tzs wrote: post #248
maerF0x0 wrote: post #80

Earlier quoted context omitted.

plz explain. I have something similar to these https://www.amazon.com/OffGrid-Blocker-Unwanted-Transfer-Pro... And it seems to charge quick enough (albeit never timed it)...

The way USB high power charging works is that unless the charger and the device agree on high power the charger just charges at the older pre-high power USB rate. That's why you can plug ancient devices into a high power charger without worry that they will get fried. The way the charger and the device agree on how much power the charger should supply involves the data lines. Thus, if you simply drill out the data li…

> It protects the device because the data lines on the charger side are not connected to the data lines on the device side.

or so we hope

Re: FBI is warning people against using public phone-charging stations

#264

Post by dotancohen »

tablespoon wrote: post #234
ghaff wrote: post #111

Earlier quoted context omitted.

Many people, including many people on this site (and, yes, including myself) wouldn't think twice about plugging into an available port if they need a charge. Maybe I don't plug into an unlabeled port in some random location where it doesn't look like it belongs, but honestly I wouldn't think twice about charging at a designated area at a conference. (Though, yeah, I'd avoid a lot of "normal" activities if I ever att…

> Many people, including many people on this site (and, yes, including myself) wouldn't think twice about plugging into an available port if they need a charge. Maybe I don't plug into an unlabeled port in some random location where it doesn't look like it belongs, but honestly I wouldn't think twice about charging at a designated area at a conference. This is the solution to that problem: https://www.amazon.com/Port…

If you're already committed to carrying Yet Another Accessory, then why not just carry a small portable charging battery. Some models are not much larger than that USB connector, and could charge the phone more than sitting babysitting a charging phone for an hour.

Re: FBI is warning people against using public phone-charging stations

#265

Post by fortuna86 »

TheNewsIsHere wrote: post #195
cuttysnark wrote: post #107

Earlier quoted context omitted.

> common knowledge to never use public chargers Perhaps here on HN. Most people will plug their smartphone into any accepting receptacle. trains, airplanes, NYC SmartLink, or ask the bartender if they can plug it in behind the bar. I still carry a DIY Altoids charger that takes a 9V battery (pulled down to proper volts for iPhone). In a battery emergency, my phone is simply on life support and I don't have to look fo…

I try to always travel with a “USB data condom”. The one I have is called a “PortaPow”, and it’s red. It was about $10 on Amazon and it’s a great investment for scenarios where I _reasonably_ trust a power-only USB port not to have been tampered with, like the built in ports on aircraft.

Can you be reasonably certain they work?

Re: FBI is warning people against using public phone-charging stations

#266

Post by codethief »

EMM_386 wrote: post #257
ghaff wrote: post #111

Earlier quoted context omitted.

Many people, including many people on this site (and, yes, including myself) wouldn't think twice about plugging into an available port if they need a charge. Maybe I don't plug into an unlabeled port in some random location where it doesn't look like it belongs, but honestly I wouldn't think twice about charging at a designated area at a conference. (Though, yeah, I'd avoid a lot of "normal" activities if I ever att…

Yes, I was in the hospital waiting room recently and they had a charging station with each type of available cable. I charged me phone, fully aware of these sorts of issues. I just went with my gut instinct that, in that environment, it's highly unlikely that the cables have been "trojanized". The FBI can warn about it, but what can you really do? You just have to trust your judgement as to what you feel are safe cha…

> but what can you really do?

Get a USB condom, for instance, practice safer charging. :)

Re: FBI is warning people against using public phone-charging stations

#267

Post by sacrosancty »

tzs wrote: post #258

I've come to think that whatever eventually replaces USB should add some separation between power and data. Let's call it MSB (Multiversal Serial Bus). Maybe something like this. MSB would define 2 connectors: a data connector and a power connector. MSB would also specify that if you have both data and power connectors they should be physically laid out in data/power pairs and would define the spacing/positioning (e.…

That's pretty much USB3-A isn't it? High speed data is separate from power and low speed data. You can have connectors with just one or the other.

Anyway, the world will be worse place with just incremental incompatible tweaks to the so-called "universal" connectors so that they're never universal because of churn. Hopefully USB-C is the end of the line forever, whatever its flaws might be.

Re: FBI is warning people against using public phone-charging stations

#268

Post by pastage »

amelius wrote: post #253
wongarsu wrote: post #174

Earlier quoted context omitted.

The malicious charger can pretend to be keyboard, mouse and screen, and just remote control the phone. Or just a keyboard, if you want to an easier implementation. At least Android phones are completely usable this way, with universal keyboard/mouse support and widespread USB-C display support. Without any confirmation steps.

If this is true, then just use a charging cable with only the two power wires in it.

What is in the connector? While the only evil usb connectors I have seen are the big ones. Putting evil in and lighting or usb-c should be more than possible.

Re: FBI is warning people against using public phone-charging stations

#269

Post by i_am_jl »

tzs wrote: post #258

I've come to think that whatever eventually replaces USB should add some separation between power and data. Let's call it MSB (Multiversal Serial Bus). Maybe something like this. MSB would define 2 connectors: a data connector and a power connector. MSB would also specify that if you have both data and power connectors they should be physically laid out in data/power pairs and would define the spacing/positioning (e.…

Why not offload this to the device?

Why doesn't my device today have an option that allows me to set the USB port to "power only"?

Re: FBI is warning people against using public phone-charging stations

#270

Post by [deleted] »

tzs wrote: post #258

I've come to think that whatever eventually replaces USB should add some separation between power and data. Let's call it MSB (Multiversal Serial Bus). Maybe something like this. MSB would define 2 connectors: a data connector and a power connector. MSB would also specify that if you have both data and power connectors they should be physically laid out in data/power pairs and would define the spacing/positioning (e.…

[deleted]
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