Cybersecurity; Data minimization; European Digital Identity Wallet; Privacy threat modeling; Unlinkability
Abstract :
[en] Digital identity wallets promise significant advancements in digital identity management by offering users a high degree of convenience, security, and control over their data disclosure. However, there is also criticism regarding their privacy guarantees, especially when used in regulated use cases that require high levels of assurance on the correctness and binding of a legal identity. In this paper, we present a comprehensive privacy model and analysis of one of the most prominent digital wallets – the European Digital Identity Wallet (EUDIW) – as specified by the Architecture and Reference Framework (ARF) and the eIDAS 2.0 regulation. We employ a suite of qualitative privacy risk assessment methods to systematically map and evaluate information flows in three key use cases. Our analysis identifies multiple privacy risks – including linkability, identifiability, and excessive attribute data disclosure – and reveals that although the ARF is designed to comply with privacy-by-design principles, inherent design choices, such as the reliance on SD-JWT and mDOC data formats, as well as the concept of a Wallet Unit Attestation (WUA), retain risks to user privacy. Building on our findings, we then highlight how advanced Privacy-Enhancing Technologies (PETs), such as (general-purpose) Zero-Knowledge Proofs (ZKPs), can reduce or mitigate some of these risks.
Research center :
Interdisciplinary Centre for Security, Reliability and Trust (SnT) > FINATRAX - Digital Financial Services and Cross-organizational Digital Transformations NCER-FT - FinTech National Centre of Excellence in Research
Disciplines :
Computer science
Author, co-author :
ABELLÁN ÁLVAREZ, Iván ✱; University of Luxembourg > Interdisciplinary Centre for Security, Reliability and Trust (SNT) > FINATRAX
HÖLZMER, Pol ✱; University of Luxembourg > Interdisciplinary Centre for Security, Reliability and Trust (SNT) > FINATRAX
FNR13342933 - DFS - Paypal-fnr Pearl Chair In Digital Financial Services, 2019 (01/01/2020-31/12/2024) - Gilbert Fridgen FNR16326754 - PABLO - Privacy-preserving Tokenisation Of Artworks, 2021 (01/06/2022-31/05/2025) - Gilbert Fridgen FNR16570468 - NCER-FT - 2021 (01/03/2023-28/02/2025) - Gilbert Fridgen
Funders :
FNR - Luxembourg National Research Fund Luxembourg's Ministry for Digitalisation
Funding number :
13342933; 16326754; 16570468
Funding text :
This research was supported in part by Luxembourg's Ministry for Digitalisation, PayPal, and the Luxembourg National Research Fund (FNR) (PEARL grant reference 13342933, PABLO grant reference 16326754, NCER-FT grant reference 16570468). For the purpose of open access and in fulfillment of the obligations arising from the grant agreements, the authors have applied a Creative Commons Attribution 4.0 International (CC BY 4.0) license to any Author Accepted Manuscript version arising from this submission. The authors acknowledge the use of Grammarly's generative AI features to enhance the clarity, grammar, and coherence of their writing by refining sentence structure.
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