Less so than we expected; a metallic case definitely reduces the signal strength, but IIRC for the one case we tried placing, the small-loop antenna directly on the case still gets you a good-enough signal to break this (pretty basic) AES implementation. Someone could definitely do more research into that, though - we only did a one-off experiment.
Good point. The case wasn't grounded but that is more common for embedded targets/laptops.
We haven't looked at attacking desktops but the fact that there is a market for tempest shielded desktops (from OSPL, etc.) is perhaps an indication that it might still be possible...
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Less so than we expected; a metallic case definitely reduces the signal strength, but IIRC for the one case we tried placing, the small-loop antenna directly on the case still gets you a good-enough signal to break this (pretty basic) AES implementation. Someone could definitely do more research into that, though - we only did a one-off experiment.
Of course, everyone uses plastic nowadays... ;-)
Was the case grounded?
Laptops are mostly plastic and some non-grounded metal. Desktops are mostly grounded steel.
Steel may be permeable enough for a tempest attack. I don't know.
Good point. The case wasn't grounded but that is more common for embedded targets/laptops.
We haven't looked at attacking desktops but the fact that there is a market for tempest shielded desktops (from OSPL, etc.) is perhaps an indication that it might still be possible...