RE: Backport of the integer overflow in the brk system call
Andreas Schuldei wrote:
> * Russell Coker (email@example.com) [031203 04:03]:
> > I have sent a message to Werner asking if the GPG smart-card device
> > could be re-implemented with a USB interface. I think that a USB
> > dongle with GPG technology would be a good option as most developer's
> > machines already have USB support.
> as discussed in depth in an earlier c't magazine (german) usb is
> not a save bus to use for security relevant applications, since
> it allows for recording and backplaying of command sequences.
What article was that?
Anyhow, a serial port or a PS/2 keyboard port is "unsafe" in the same way. A secure card reader solution would use a challenge/response procedure, so a simple replay attack could never be successful. Additionally, a secure card reader device would be sealed (and deactivate/destroy itself upon physical break-in) and require the user to enter a PIN/password to use the cryptographic key stored on the card. What would make such a card reader solution particularly unsafe when connected through USB?