A Survey on Security and Privacy in
Blockchain-based Central Bank Digital Currencies

Yunyoung Lee¹, Bumho Son¹, Seongwan Park¹, Jaewook Lee¹, and Huisu Jang²⁺

¹Seoul National University, Seoul, Republic of Korea

{tommja, andymogul, sucre87, jaewook}@snu.ac.kr

²Soongsil University, Seoul, Republic of Korea

Yej523@ssu.ac.kr

Abstract

The increasing interest in Central Bank Digital Currencies has heightened the need for the suitable security technologies for preserving the privacy of users of the CBDC. Although the CBDC system architecture is deeply related to the legacy payment system and the public blockchain system, security and privacy issues of the CBDC are completely different from those of the existing systems as the purpose of the CBDC is to achieve auditable privacy. We demonstrate the taxonomy of the security and privacy issues in CBDC system according to the following areas: identity, transaction, consensus and auditability. We also emphasize the research gaps in the fields stem from the CBDC’s unique characteristics including the authorized audit risk problem and the cross-border payments problem. This study contributes to the current understanding of the security and privacy concerns of CBDCs and addresses the remaining gaps in this field of research.

Keywords: central bank digital currencies, middle-ground blockchain, privacy, security

+: Corresponding author: Huisu Jang
School of Finance, Soongsil University, Seoul, Republic of Korea, 06978, Tel: +82-(0)2-828-7389

Journal of Internet Services and Information Security (JISIS), 11(3): 16-29, August 2021

Received: June 12, 2021; Accepted: August 6, 2021; Published: August 31, 2021

DOI: 10.22667/JISIS.2021.08.31.016 [pdf]