RSA-4096 / ElGamal-3072 – Physical Side-Channel Key-Extraction Attacks [pdf]

More evidence that if you can't physically secure the hardware, all bets are off. The ability to conduct the attack through an Ethernet cable does add a new dimension to the attack surface, however.

I guess this is also another reason why TEMPEST defines shielding standards to help mitigate these side-channel attacks.