3 ms·

This would still not pick up malicious surface-mount devices. Imagine a subverted NOR FLASH device with malicious firmware booting your board-management device

This would still not pick up malicious surface-mount devices. Imagine a subverted NOR FLASH device with malicious firmware booting your board-management device. Its still a SPI FLASH with the same (apparent) device id. The contents would just be different.

alias_neo 8y ago
The technology shown here is working at a different level; is looking at the PCB, trace by trace and identifying components and connections, layer by layer and verifying it against the design. It's purpose is to ensure that designs aren't modified in manufacture. What you're talking about is a software problem, and should be carried out in addition to this. The first idea that comes to mind is that I would sign the contents of the flash devices and have them verified once the board layout has been verified. Essentially, you'd have your board schematic, and then a signature "schematic" of firmware to verify against. Of course, you'd also need a way of signing the schematic/signature list to verify those once they're updated.
- rasz 8y ago
  Yes, in other words technology shown here is useless.
  - alias_neo 8y ago
    I'm not sure what gives you that impression. In this case, the technology would have identified this additional component added out-of-spec. Once you've identified that a component that doesn't belong has been added you don't need to bother identifying any software attacks, it's already compromised.
    - rasz 8y ago
      What makes you think this component (if it existed) was visually different from component it replaced on the pcb?
- exoesquitur 8y ago
  Passive components like a line conditioning resistor or cap could be changed out with an identical looking malicious component. Such a chip could perform effective MITM attacks against anything that talks on a serial line such as I2C, SPI, etc. This is pretty much a universal zero day for on board controllers, FPGA's, and anything that loads its boot code unencrypted.

alias_neo 8y ago

The technology shown here is working at a different level; is looking at the PCB, trace by trace and identifying components and connections, layer by layer and verifying it against the design. It's purpose is to ensure that designs aren't modified in manufacture. What you're talking about is a software problem, and should be carried out in addition to this. The first idea that comes to mind is that I would sign the contents of the flash devices and have them verified once the board layout has been verified. Essentially, you'd have your board schematic, and then a signature "schematic" of firmware to verify against. Of course, you'd also need a way of signing the schematic/signature list to verify those once they're updated.

rasz 8y ago
Yes, in other words technology shown here is useless.
- alias_neo 8y ago
  I'm not sure what gives you that impression. In this case, the technology would have identified this additional component added out-of-spec. Once you've identified that a component that doesn't belong has been added you don't need to bother identifying any software attacks, it's already compromised.
  - rasz 8y ago
    What makes you think this component (if it existed) was visually different from component it replaced on the pcb?
exoesquitur 8y ago
Passive components like a line conditioning resistor or cap could be changed out with an identical looking malicious component. Such a chip could perform effective MITM attacks against anything that talks on a serial line such as I2C, SPI, etc. This is pretty much a universal zero day for on board controllers, FPGA's, and anything that loads its boot code unencrypted.