3 ms·

Easy way to detect this without an RF detector - use a "usb charge doctor" which is a super cheap voltage and current measurement tool for USB. If the cable dra

Easy way to detect this without an RF detector - use a "usb charge doctor" which is a super cheap voltage and current measurement tool for USB. If the cable draws current with nothing attached, dissect it. Incidentally, my theory about the website and product is that this is a firmware reuse of a fleet tracking product. The manufacturer is likely an electronics manufacturing outfit that adapted the layout to match the new application but didn't have in-house firmware developers and instead reused a popular low-end fleet tracker firmware for the same chip. These are used for stuff like taxi dispatch or package pickup so you can see the entire fleet on a map and call whoever is closest to your destination. It doesn't need precise location.

speaker1 7y ago
usb-c cables seem to drain power, at least both I have, though one of them has LED.
- NullPrefix 7y ago
  Type C cables have chips in them. Not a dumb wire. That's by design
  - antsar 7y ago
    That design, in this context, seems bad for security...
- xoa 7y ago
  I've never tried it now that I think about it, but how standardized is the USB-C cable drain? I would assume that, with perhaps some minimal difference for length, all normal in-spec cables would be pretty similar, but I don't actually know that and would be curious if anyone has checked a few. If there is a standard baseline though then the OP's advice doesn't meaningfully change, it just becomes "If the cable draws current over the baseline with nothing attached, dissect it" rather then "if it draws any at all". Any spy chip would still have to be on top of whatever else is needed to make the cable work at all, so it's not really a different problem unless standard cables have enough delta between them to hide a spy chip drain in. And even if that's true between manufacturers, if within a single manufacturer cables were pretty steady that might merely become a reason to source exclusively from one/a few reliable ones that stable baseline draws can be established for?
michaelt 7y ago
Incidentally, my theory about the website and product is that this is a firmware reuse of a fleet tracking product. Yeah, there are already off-the-shelf products like [1] that combine GPS, battery and SMS sending. Presumably this product is a variant of one of those. [1] https://www.ebay.co.uk/itm/GPS-Tracker/223443762010 https://www.ebay.co.uk/itm/GPS-Tracker/223443762010

speaker1 7y ago

usb-c cables seem to drain power, at least both I have, though one of them has LED.

NullPrefix 7y ago
Type C cables have chips in them. Not a dumb wire. That's by design
- antsar 7y ago
  That design, in this context, seems bad for security...
xoa 7y ago
I've never tried it now that I think about it, but how standardized is the USB-C cable drain? I would assume that, with perhaps some minimal difference for length, all normal in-spec cables would be pretty similar, but I don't actually know that and would be curious if anyone has checked a few. If there is a standard baseline though then the OP's advice doesn't meaningfully change, it just becomes "If the cable draws current over the baseline with nothing attached, dissect it" rather then "if it draws any at all". Any spy chip would still have to be on top of whatever else is needed to make the cable work at all, so it's not really a different problem unless standard cables have enough delta between them to hide a spy chip drain in. And even if that's true between manufacturers, if within a single manufacturer cables were pretty steady that might merely become a reason to source exclusively from one/a few reliable ones that stable baseline draws can be established for?

michaelt 7y ago

Incidentally, my theory about the website and product is that this is a firmware reuse of a fleet tracking product. Yeah, there are already off-the-shelf products like [1] that combine GPS, battery and SMS sending. Presumably this product is a variant of one of those. [1] https://www.ebay.co.uk/itm/GPS-Tracker/223443762010 https://www.ebay.co.uk/itm/GPS-Tracker/223443762010