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Responsible Vulnerability Disclosure in Cryptocurrencies

cracked bitcoin, illustration

Credit: The Image Foundation

Despite the focus on operating in adversarial environments, cryptocurrencies have suffered a litany of security and privacy problems. Sometimes, these issues are resolved without much fanfare following a disclosure by the individual who found the hole. In other cases, they result in costly losses due to theft, exploits, unauthorized coin creation, and destruction. These experiences provide regular fodder for outrageous news headlines. In this article, we focus on the disclosure process itself, which presents unique challenges compared to other software projects.15 To illustrate, we examine some recent disclosures and discuss difficulties that have arisen.

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Key Insights


While Bitcoin is the best known, more than 2,000 cryptocurrencies are in circulation, collectively valued at $350 billion as of August 2020.6 Figure 1 conceptualizes the landscape as a stack. While the details differ, at the lowest level, each cryptocurrency system is designed to achieve common security goals: transaction integrity and availability in a highly distributed system whose participants are incentivized to cooperate.38 Users interact with the cryptocurrency system via software "wallets" that manage the cryptographic keys associated with the coins of the user. These wallets can reside on a local client machine or be managed by an online service provider. In these applications, authenticating users and maintaining confidentiality of cryptographic key material are the central security goals. Exchanges facilitate trade between cryptocurrencies and between cryptocurrencies and traditional forms of money. Wallets broadcast cryptocurrency transactions to a network of nodes, which then relay transactions to miners, who in turn validate and group them together into blocks that are appended to the blockchain.


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