ZK-eSIM improves privacy in eSIM profile provisioning from operators
ZK-eSIM: A Privacy-Centric Zero-Knowledge Approach for eSIM Provisioning
Cryptography and Security
Summary
When you order and download eSIM profiles, your device can share permanent IDs that let mobile operators and infrastructure link different orders to you, reducing your privacy. The authors designed ZK-eSIM, a new method that hides these identifiers using zero-knowledge proofs and temporary credentials, so your identity and activity can’t be easily tracked. It also allows authorized parties to trace users only when necessary through a joint approval process. They tested their approach on standard hardware and found the extra privacy does not add too much delay or complexity.
What this means in practice
- •For mobile network operators: Protect subscriber privacy during eSIM profile provisioning while keeping controlled traceability options.
- •For security system architects: Design privacy-preserving credential provisioning systems using zero-knowledge proofs and pseudonymous credentials.
Authors
Liza Ahmad, Quan Shi, Joshua Haworth, Yilu Dong, Prosanta Gope, Behzad Abdolmaleki, Syed Rafiul Hussain
Abstract
GSMA Remote SIM Provisioning (RSP) enables over-the-air delivery of eSIM profiles, but it exposes long-lived identifiers during profile ordering and download. In particular, stable device identifiers (e.g., EID), profile identifiers, and long-lived certificate material enable mobile operators and profile-delivery infrastructure to link provisioning events to the same eUICC and, when combined with account records, to the same subscriber. This undermines subscriber anonymity and enables cross-session tracking. We present ZK-eSIM, a privacy-preserving redesign that achieves subscriber anonymity and provisioning-session unlinkability while retaining accountable traceability by exception. ZK-eSIM (i) replaces direct disclosure of device identifiers with a zero-knowledge proof of device validity and eligibility; (ii) enforces session unlinkability through short-lived, one-time pseudonymous credentials and per-session identifiers to prevent cross-session tracking; and (iii) provides privacy-preserving accountable traceability through a jointly authorised escrow mechanism, so that no single entity can unilaterally deanonymise a user. We formalise a multi-entity, honest-but-curious threat model and prove subscriber anonymity and the unlinkability of provisioning sessions under standard cryptographic assumptions. We implement a Java Card applet on a test eUICC to evaluate performance on commodity hardware with a modified LPA and SM-DP+ server. Our experiments quantify end-to-end cryptographic overhead relative to conventional RSP, confirming that ZK-eSIM adds only practical overhead, closing a critical privacy gap while preserving deployability within existing GSMA roles and interfaces.