Blockchain relies on the underlying peer-to-peer (P2P) networking to broadcast and get up-to-date on the blocks and transactions. Because of the blockchain operations’ reliance on the information provided by P2P networking, it is imperative to have high P2P connectivity for the quality of the blockchain system operations and performances. High P2P networking connectivity ensures that a peer node is connected to multiple other peers providing a diverse set of observers of the current state of the blockchain and transactions. However, in a permissionless Bitcoin cryptocurrency network, using the peer identifiers – including the current approach of counting the number of distinct IP addresses and port numbers – can be ineffective in measuring the number of peer connections and estimating the networking connectivity. Such current approach is further challenged by the networking threats manipulating identities. We build a robust estimation engine for the P2P networking connectivity by sensing and processing the P2P networking traffic. We take a systematic approach to study our engine and analyze the followings: the different components of the connectivity estimation engine and how they affect the accuracy performances, the role and the effectiveness of an outlier detection to enhance the connectivity estimation, and the engine’s interplay with the Bitcoin protocol. We implement a working Bitcoin prototype connected to the Bitcoin mainnet to validate and improve our engine’s performances and evaluate the estimation accuracy and cost efficiency of our connectivity estimation engine. Our results show that our scheme effectively counters the identity-manipulations threats, achieves 96.4% estimation accuracy with a tolerance of one peer connection, and is lightweight in the overheads in the mining rate, thus making it appropriate for the miner deployment.
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This content will become publicly available on January 12, 2025
Bijack: Breaking Bitcoin Network with TCP Vulnerabilities
Recent studies have shown that compromising Bitcoin’s peer-to-peer network is an effective way to disrupt the Bitcoin service. While many attack vectors have been uncovered such as BGP hijacking in the network layer and eclipse attack in the application layer, one significant attack vector that resides in the transport layer is largely overlooked. In this paper, we investigate the TCP vulnerabilities of the Bitcoin system and their consequences. We present Bijack, an off-path TCP hijacking attack on the Bitcoin network that is able to terminate Bitcoin connections or inject malicious data into the connections with only a few prior requirements and a limited amount of knowledge. This results in the Bitcoin network topology leakage, and the Bitcoin nodes isolation.
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- Award ID(s):
- 2247561
- NSF-PAR ID:
- 10499541
- Publisher / Repository:
- Springer Nature Switzerland
- Date Published:
- Journal Name:
- Computer Security -- ESORICS 2023
- Page Range / eLocation ID:
- 306--326
- Format(s):
- Medium: X
- Location:
- Cham
- Sponsoring Org:
- National Science Foundation
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