Re:Researchers can steal data during homomorphic encryption
by schoen on Friday March 04, 2022 @04:20PM
(#30560740)
It feels plausible to me that homomorphic encryption would be especially vulnerable to side-channel attacks because its schemes are so computation-heavy. I don't have a clear mental model for this, but it feels like there would be a lot of opportunities for attackers to detect data dependencies at the beginning of the process (if they have access to observe a relevant channel).
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Re:Researchers can steal data during homomorphic encryption
by karulont on Friday March 04, 2022 @05:08PM
(#30561271)
The encryption is data dependent. The homomorphic computation itself cannot be data dependent. Homomorphic encryption says that even if you see all the intermediate encrypted values, you will not know what the encrypted input or output value is. So side-channels do not matter for the computationally heavy evaluation part. In this paper they attacked the encryption part.
Re:Researchers can steal data during homomorphic encryption
by schoen on Friday March 04, 2022 @07:33PM
(#30562549)
Sorry, I meant the initial preparation of the encrypted data. I believe that this step is also typically rather computationally heavy, although maybe less so than the later computation over the encrypted data.