Passive and active attackers in noiseless privacy

05/02/2019
by   Damien Desfontaines, et al.
0

Differential privacy offers clear and strong quantitative guarantees for privacy mechanisms, but it assumes an attacker that knows all but one records of the dataset. This assumption leads in many applications to an overapproximation of an attacker's actual strength. This can lead to over-cautiously chosen noise parameters, which can in turn lead to unnecessarily poor utility. Recent work has made significant steps towards privacy in the presence of limited background knowledge. Definitions like noiseless privacy are modeling a weaker attacker who has uncertainty about the data. In this technical report, we show that existing definitions implicitly assume an active attacker, who can not only see, but control some of the data. We argue that in some cases, it makes sense to consider a passive attacker, who has some knowledge about the data, but cannot influence it. We propose an alternative definition to capture this attacker model, we study the link between these two alternatives, and we show some consequences of this distinction on the security of thresholding schemes.

READ FULL TEXT

page 1

page 2

page 3

page 4

research
09/08/2022

Reconstruction Attacks on Aggressive Relaxations of Differential Privacy

Differential privacy is a widely accepted formal privacy definition that...
research
08/17/2018

Cardinality Estimators do not Preserve Privacy

Cardinality estimators like HyperLogLog are sketching algorithms that es...
research
06/04/2019

SoK: Differential Privacies

Shortly after its introduction in 2006, differential privacy became the ...
research
06/09/2021

Fundamental Privacy Limits in Bipartite Networks under Active Attacks

This work considers active deanonymization of bipartite networks. The sc...
research
09/21/2018

Understanding Compressive Adversarial Privacy

Designing a data sharing mechanism without sacrificing too much privacy ...
research
01/10/2023

Improving unlinkability in C-ITS: a methodology for optimal obfuscation

In this paper, we develop a new methodology to provide high assurance ab...
research
05/05/2021

Breaking and Fixing Unlinkability of the Key Agreement Protocol for 2nd Gen EMV Payments

To address privacy problems with the EMV standard, EMVco proposed a Blin...

Please sign up or login with your details

Forgot password? Click here to reset