Security and Privacy of Mobile Wallet Users in Bitcoin, Dash, Monero, and Zcash

Mobile devices play an increasingly important role in the cryptocurrency ecosystem, yet their privacy guarantees remain unstudied. To verify transactions, they either trust a server or use simple payment verification.

First, we review the security and privacy of popular Android wallets for Bitcoin and the three major privacy-focused cryptocurrencies (Dash, Monero, Zcash). Then, we investigate the network-level properties of cryptocurrencies and propose a method of transaction clustering based on timing analysis. We implement and test our method on selected wallets and show that a moderately resourceful attacker can correlate transactions issued from one device with relatively high accuracy.