6 ms·

"Tip: Additionally, you may use a cord to attach a USB key to your wrist. Then insert the key into your computer and start usbkill." This line particularly cau

"Tip: Additionally, you may use a cord to attach a USB key to your wrist. Then insert the key into your computer and start usbkill." This line particularly caught my eye. I wonder what's the percentage of people (I'm presuming people working in security or those who are trying to avoid detection) go to this extreme? Is is even extreme?

berkas1 6y ago
I don't think that wrist-key is an extreme (never seen it actually, but I still think this solution is a cautious one). For me an extreme measure would be to modify my motherboard in a way that I could connect RAM to my wrist and tear it away when necessary.
- nkrisc 6y ago
  Now that would be interesting: have your RAM strapped to your wrist and connected to your Mobo by a breakaway cable. Bonus points if they cut it when the tackle you because they thought it was a deadman switch, like mentioned in the link.
baq 6y ago
not a security expert but a commonly heard phrase is 'depends on your threat model' :)
moritonal 6y ago
"To prevent Ulbricht from encrypting or deleting files on the laptop he was using to run the site as he was arrested, two agents pretended to be quarreling lovers. When they had sufficiently distracted him, according to Joshuah Bearman of Wired, a third agent grabbed the laptop while Ulbricht was distracted by the apparent lovers' fight and handed it to agent Thomas Kiernan. Kiernan then inserted a flash drive in one of the laptop's USB ports, with software that copied key files." https://en.wikipedia.org/wiki/Ross_Ulbricht https://en.wikipedia.org/wiki/Ross_Ulbricht
- daffy 6y ago
  > Kiernan then inserted a flash drive in one of the laptop's USB ports, with software that copied key files. How exactly does this work? Is there a sort of software that runs automatically when you insert the stick, or did he have to click on it?
  - sumtechguy 6y ago
    You can present yourself as a standard file system or some device you know has a known exploit in the driver on the other side. Then on the USB 'drive' side you have a full out arm CPU. It can issue commands too as it is connected to the serial bus. Many USB drives already have small embedded CPU in them.
    - R0b0t1 6y ago
      >Many USB drives already have small embedded CPU in them. For most common hardware this is just an 8051 variant that sets up the USB and DMA peripherals. It's easy enough to get something more powerful, but I am doubtful you'd want to reuse consumer hardware.
      - sumtechguy 6y ago
        The 8051 is a decently capable CPU (it is the cpu at the heart of the furby toy). At one point they built whole computer ecosystems around it. Remember the point here is to take over the computer not have a full out modern OS. They USB manufactures use them because they work well on low power and are decently cheap and small. Now most usb sticks do not do much more than like you say. But that would not stop someone from reflashing the firmware in it who is making one of these things. The use case here is different than what most people would use it for. Sometimes you will see an older ARM design too.
        R0b0t1 6y ago
        Mfrs use them because they are not patent encumbered. There are some fairly high power 8051 clones, true. But in most applications they are barely sufficient. In this case any kind of MCU is making life harder than it needs to be.
emiliobumachar 6y ago
How about a bluetooth dongle in your pocket? Less visible, and unless there hostiles know about it, they will separate you from the computer. A phone could work. An apparent car key would be better. Best would be a piece of clothing, like a belt.
- paledot 6y ago
  That would work great for half an hour, until your Bluetooth connection drops for no reason, the dongle pairs with your car or phone instead, decides it's a headset now, or one of the hundred other things that inevitably go wrong with Bluetooth.
  - sumtechguy 6y ago
    hehe, Do not think like an engineer in this case. Think like someone who only has to get it right once but can try 100 times. So even if you have a flake connection. Just so long as it works that 'one time'. You are good.
- nullc 6y ago
  There are bluetooth low energy key fobs that work for this.

berkas1 6y ago

I don't think that wrist-key is an extreme (never seen it actually, but I still think this solution is a cautious one). For me an extreme measure would be to modify my motherboard in a way that I could connect RAM to my wrist and tear it away when necessary.

nkrisc 6y ago
Now that would be interesting: have your RAM strapped to your wrist and connected to your Mobo by a breakaway cable. Bonus points if they cut it when the tackle you because they thought it was a deadman switch, like mentioned in the link.

baq 6y ago

not a security expert but a commonly heard phrase is 'depends on your threat model' :)

moritonal 6y ago

"To prevent Ulbricht from encrypting or deleting files on the laptop he was using to run the site as he was arrested, two agents pretended to be quarreling lovers. When they had sufficiently distracted him, according to Joshuah Bearman of Wired, a third agent grabbed the laptop while Ulbricht was distracted by the apparent lovers' fight and handed it to agent Thomas Kiernan. Kiernan then inserted a flash drive in one of the laptop's USB ports, with software that copied key files." https://en.wikipedia.org/wiki/Ross_Ulbricht https://en.wikipedia.org/wiki/Ross_Ulbricht

daffy 6y ago
> Kiernan then inserted a flash drive in one of the laptop's USB ports, with software that copied key files. How exactly does this work? Is there a sort of software that runs automatically when you insert the stick, or did he have to click on it?
- sumtechguy 6y ago
  You can present yourself as a standard file system or some device you know has a known exploit in the driver on the other side. Then on the USB 'drive' side you have a full out arm CPU. It can issue commands too as it is connected to the serial bus. Many USB drives already have small embedded CPU in them.
  - R0b0t1 6y ago
    >Many USB drives already have small embedded CPU in them. For most common hardware this is just an 8051 variant that sets up the USB and DMA peripherals. It's easy enough to get something more powerful, but I am doubtful you'd want to reuse consumer hardware.
    - sumtechguy 6y ago
      The 8051 is a decently capable CPU (it is the cpu at the heart of the furby toy). At one point they built whole computer ecosystems around it. Remember the point here is to take over the computer not have a full out modern OS. They USB manufactures use them because they work well on low power and are decently cheap and small. Now most usb sticks do not do much more than like you say. But that would not stop someone from reflashing the firmware in it who is making one of these things. The use case here is different than what most people would use it for. Sometimes you will see an older ARM design too.
      - R0b0t1 6y ago
        Mfrs use them because they are not patent encumbered. There are some fairly high power 8051 clones, true. But in most applications they are barely sufficient. In this case any kind of MCU is making life harder than it needs to be.

emiliobumachar 6y ago

How about a bluetooth dongle in your pocket? Less visible, and unless there hostiles know about it, they will separate you from the computer. A phone could work. An apparent car key would be better. Best would be a piece of clothing, like a belt.

paledot 6y ago
That would work great for half an hour, until your Bluetooth connection drops for no reason, the dongle pairs with your car or phone instead, decides it's a headset now, or one of the hundred other things that inevitably go wrong with Bluetooth.
- sumtechguy 6y ago
  hehe, Do not think like an engineer in this case. Think like someone who only has to get it right once but can try 100 times. So even if you have a flake connection. Just so long as it works that 'one time'. You are good.
nullc 6y ago
There are bluetooth low energy key fobs that work for this.