Deanonymisation of Clients in Bitcoin P2P Network

Abstract

Bitcoin is a digital currency which relies on a distributed set of miners to mint coins and on a peer-to-peer network to broadcast transactions. The identities of Bitcoin users are hidden behind pseudonyms (public keys) which are recommended to be changed frequently in order to increase transaction unlinkability.We present an efficient method to deanonymize Bitcoin users, which allows to link user pseudonyms to the IP addresses where the transactions are generated. Our techniques work for the most common and the most challenging scenario when users are behind NATs or firewalls of their ISPs. They allow to link transactions of a user behind a NAT and to distinguish connections and transactions of different users behind the same NAT. We also show that a natural countermeasure of using Tor or other anonymity services can be cut-off by abusing anti-DoS countermeasures of the Bitcoin network. Our attacks require only a few machines and have been experimentally verified. The estimated success rate is between 11% and 60% depending on how stealthy an attacker wants to be. We propose several countermeasures to mitigate these new attacks.

Deviating From the Cybercriminal Script: Exploring Tools of Anonymity (Mis)Used by Carders on Cryptomarkets

“…Tools such as BitCluster 15 , Chainalysis 16 and Elliptic 17 analyse the blockchain to group Bitcoin transactions together that are seemingly related and find the origins of payments. Biryukov, Khovratovich and Pustogarov (2014) have shown how to deanonymise a significant fraction of Bitcoin users and in this way linking user's pseudonyms to their IP addresses. Reid and Harrigan (2013) suggest that a user directory can be partly built by associating Bitcoin users and their public keys with offline information.…”

Listening to Whispers of Ripple: Linking Wallets and Deanonymizing Transactions in the Ripple Network

“…Thus, recent works [63,75,77,81] have proposed simple heuristics to thwart anonymity in Bitcoin. In a somewhat different direction, other recent works [47,61] show the possibility of identifying ownership relationships between Bitcoin wallets and IP addresses. As Bitcoin heuristics do not fit transaction networks, our novel heuristics are focused and have special interest for transaction networks such as Ripple, including the integration of several available cryptocurrencies.…”

“…For example, in the case of the Bitcoin network, a series of works [47,58,61] sulting from these techniques since if a Bitcoin wallet is deanonymized, the complete cluster (including Ripple and other cryptocurrency wallets) is deanonymized. Ripple transactions are collected by Ripple validator servers.…”

Systematizing Decentralization and Privacy: Lessons from 15 Years of Research and Deployments

“…This allows to trace money flows and avoid doublespending; but on the downside if a pseudonym is ever deanonymized (e.g. [21]), all actions from the person would be revealed. A number of decentralized systems, ranging from mix-nets [36,45], to DC-nets [37], to Tor [57], provide some degree of anonymity.…”