Privacy protocols

TL;DR

This paper discusses the complexities and vulnerabilities of privacy protocols, highlighting how privacy attacks can undermine privacy without compromising underlying security, especially in the context of political influence campaigns.

Contribution

It introduces the nuanced landscape of privacy protocol vulnerabilities, emphasizing the blurred boundaries between privacy-preserving mechanisms and privacy attacks.

Findings

Privacy attacks can bypass cryptographic security.

Privacy vulnerabilities are exploited in political influence campaigns.

Privacy protocols face complex, multi-level covert threats.

Abstract

Security protocols enable secure communication over insecure channels. Privacy protocols enable private interactions over secure channels. Security protocols set up secure channels using cryptographic primitives. Privacy protocols set up private channels using secure channels. But just like some security protocols can be broken without breaking the underlying cryptography, some privacy protocols can be broken without breaking the underlying security. Such privacy attacks have been used to leverage e-commerce against targeted advertising from the outset; but their depth and scope became apparent only with the overwhelming advent of influence campaigns in politics. The blurred boundaries between privacy protocols and privacy attacks present a new challenge for protocol analysis. Covert channels turn out to be concealed not only below overt channels, but also above: subversions, and the level-below attacks are supplemented by sublimations and the level-above attacks.