USB killer

It was an ordinary gloomy winter morning, my colleagues and I, as usual, drank morning coffee, shared news, and nothing signaled trouble. But then a friend told me ... more quote from skype chat:

I once read an article as a guy in the subway pulled a flash bag from 128 in the subway net from the mesh pocket, on which 128 was written. He came home, put it in a laptop -> he burned the floor of the computer ... He wrote on a flash drive 129 and now wears his bag in the outer pocket ...

A picture to attract attention:



Since I work in an enterprise that develops and manufactures electronics, my colleagues and I began to actively discuss options for implementing such a flash drive, which “would burn a half-computer.” There were a lot of hardcore, fantastic, and also very real options . And everything would have ended with this fun discussion, if I had not intended to order the manufacture of printed circuit boards for my other projects.

So, the USB interface of a computer, as a rule, includes a USB connector -> ESD diodes (protection against static) -> filter elements -> security elements in the chip itself, containing the physical layer of the USB interface. In modern USB computers, “physics” is almost integrated into the processor itself; in computers a bit older, north-south bridges are responsible for USB. The task of the developed flash drive is to burn the whole thing , burn the USB port at least.

Within a week, I developed a very specific circuitry implementation, ordered components, and after several months of waiting for the components, a fully functional prototype was assembled. The idea itself was tested and everything that was possible was “burned”.



Further, printed circuit boards in China were developed and ordered, a combat prototype was mounted.

Hand-soldered by me, the installer of me is so-so.





It was made under the body of a conventional flash drive.



The principle of operation of the flash drive itself is quite simple. When connected to the USB port, the inverting DC / DC converter starts up and charges the capacitors to a voltage of -110V, when this voltage is reached, the DC / DC is turned off and the field effect transistor is opened through which -110V is applied to the signal lines of the USB interface. Further on fallingincreasing the voltage across the capacitors to -7V, the transistor closes and starts DC / DC. And so in a cycle until everything breaks through. The inquiring mind of a reader familiar with electronics has already figured out why a negative voltage is used, for others I will explain that it is easier to switch negative voltage, since an N-channel field effect transistor is needed, which, unlike a P-channel, can have a much larger current with the same dimensions.

I will not speak about the scope, but a former colleague says that it’s like an atomic bomb, it’s cool to have it, but you can’t use it.