Comment on Speculative Dereferencing of Registers: Reviving Foreshadow [pdf]parentComments−xxs6yYou can have the fan on fixed rpms, hence the only side channel is that the machine has power.−mschuster916yThere's more. Vibration and electromagnetic emissions (TEMPEST) are also viable side channels. Or ultrasound in speakers to cross airgaps.−paholg6yBut that would be wasteful and needlessly noisy. The point was that there is no need.
Comments
You can have the fan on fixed rpms, hence the only side channel is that the machine has power.
There's more. Vibration and electromagnetic emissions (TEMPEST) are also viable side channels. Or ultrasound in speakers to cross airgaps.
But that would be wasteful and needlessly noisy. The point was that there is no need.