[Cryptech Tech] [FORGED] Fwd: Status tamper detection and MKM erasure (low dose gamma ray)

[Peter Gutmann]

Richard Lamb <slamb at xtcn.com> writes:

>I have ran across a relatively simple but effective protection against
>attempts to discern memory states using low dose gamma rays such as those
>from a lab Co-60 source.

Do you mean "discern" or "affect"?  Ionizing radiation will cause single-event
upsets, which is disastrous for non-hardened crypto (as well as permanent
damage from things like neutrons, but that's more detectable), but how do you
discern memory states with it?

>Only caveat I would point out is this bit flipping has also been used in the
>standard tamper detection chip used by many HSM vendors (Dallas semi.. I need
>to look up number). So it may be fall under some IPR from that chip maker.

I wrote about bit-flipping defences in the late 1990s, and I believe it was
used before then but not talked about much, so either the patents will be
close to expiring or there's prior art for them.

Peter.