Cryptology ePrint Archive: Report 2018/836

Pitchforks in Cryptocurrencies: Enforcing rule changes through offensive forking- and consensus techniques

Aljosha Judmayer and Nicholas Stifter and Philipp Schindler and Edgar Weippl

Abstract: The increasing number of cryptocurrencies, as well as the rising number of actors within each single cryptocurrency, inevitably leads to tensions between the respective communities. As with open source projects, (protocol) forks are often the result of broad disagreement. Usually, after a permanent fork both communities ``mine'' their own business and the conflict is resolved. But what if this is not the case? In this paper, we outline the possibility of malicious forking and consensus techniques that aim at destroying the other branch of a protocol fork. Thereby, we illustrate how merged mining can be used as an attack method against a permissionless PoW cryptocurrency, which itself involuntarily serves as the parent chain for an attacking merge mined branch of a hard fork.

Category / Keywords: cryptographic protocols /

Original Publication (in the same form): ESORICS CBT 2018

Date: received 5 Sep 2018

Contact author: ajudmayer at sba-research org

Available format(s): PDF | BibTeX Citation

Version: 20180906:205028 (All versions of this report)

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