Figure 2 - uploaded by Jiarun Hu
Content may be subject to copyright.
Historical Price of Bitcoin during Mt. Gox Hack in 2014 9 (Data source: Coinmarketcap.com)

Historical Price of Bitcoin during Mt. Gox Hack in 2014 9 (Data source: Coinmarketcap.com)

Source publication
Article
Full-text available
Security breaches of the cryptocurrency exchanges usually cause the price fluctuation in the market. Approximately one hundred cryptocurrency thefts, including hacks and scams, has occurred since 2012 to 2018, half of which are hacks of Bitcoin. Based on the thirty Bitcoin hacks, this study portrays the general price pattern during the hack. And it...

Citations

... In another notable incident, hackers stole approximately 120 thousand bitcoins from the Hong Kong-based exchange known as "Bitfinex," equivalent to approximately US$72 million at the time . Bitcoin prices decreased by nearly 23% following the dissemination of news regarding this incident (Hu et al., 2020). Furthermore, a significant attack was launched against the South Korean exchange Youbit. ...
... However, with the recent bearish period within the crypto ecosystem, the slope has turned negative. Fears for inflation within risk markets, regulatory uncertainty, numerous attacks and hacks caused increasing diffidence and uncertainty in cryptoassets, see [18] and [10] . This has caused investors to re-evaluate expectations and reprice the risk of DAO tokens. ...
Preprint
Full-text available
As of August 2022, blockchain-based assets boast a combined market capitalisation exceeding one trillion USD, among which the most prominent are the decentralised autonomous organisation (DAO) tokens associated with decentralised finance (DeFi) protocols. In this work, we seek to value DeFi tokens using the canonical multiples and Discount Cash Flow (DCF) approaches. We examine a subset of DeFi services including decentralised exchanges (DEXs), protocol for loanable funds (PLFs), and yield aggregators. We apply the same analysis to some publicly traded firms and compare them with DeFi tokens of the analogous category. Interestingly, despite the crypto bear market lasting for more than one year as of August 2022, both approaches evidence overvaluation in DeFi.
... Around 473 million U.S. dollars' worth of bitcoin (around 850 Bitcoin) was stolen from the company's digital vaults [59]. Another obvious example is what happened to the Hong Kong-based exchange "Bitfinex", where 120 thousand bitcoin (around US $72 million at that time) was stolen by hackers causing the price of bitcoin to plunge just under 23% after the news about this incident had broken out [60]. Moreover, another big cyber-attack occurred against the South Korean exchange Youbit, which closed down and entered into bankruptcy after stealing almost 17% of the exchange bitcoin assets [61]. ...
Article
Full-text available
In this article, the authors aim to clarify the ambiguities surrounding important aspects of cryptocurrencies. The use of cryptocurrencies has been increasingly on the rise. Hence, the importance of writing this article which primarily aims to simplify the tricky and complex terms related to this subject. This article has been approached from a conceptual, technical and legal viewpoint. It has been divided into the following three parts: (1) concept of cryptocurrency and its underlying technologies, including all the relevant definitions and meanings; (2) the related mechanism and how blockchain operates in the cryptocurrency world, which requires simplified and easy-to-understand terms and the process that takes place in the so-called blockchain ledger; (3) the legal challenges facing cryptocurrencies. This part pinpoints the most pressing legal issues concerning this virtual form of money. The legal part also aims to highlight the significant results and recommendations for the readers and policymakers to overcome the legal challenges and achieve the ultimate goal of this technology, taking into consideration the risks associated with this digital asset of exchange. In this connection, researchers in different parts of the world have endeavoured to reach and present their findings along with their suggestions and recommendations to improve the current status of this relatively nascent technology.
... In 2016, attackers managed to attack 'The DAO' and stolen over 50 million USD of Ethers (the native cryptocurrency of Ethereum) [7]. Bitfinex, a cryptocurrency exchange, lost about 120,000 Bitcoins in 2016 [8]. In 2018, five blockchain-based cryptocurrencies lost 5 million USD because of 51% attack [9]. ...
Preprint
Bitcoin and Ethereum are the top two blockchain-based cryptocurrencies whether from cryptocurrency market cap or popularity. However, they are vulnerable to selfish mining and stubborn mining due to that both of them adopt Proof-of-Work consensus mechanism. In this paper, we develop a novel Markov model, which can study selfish mining and seven kinds of stubborn mining in both Bitcoin and Ethereum. The formulas are derived to calculate several key metrics, including relative revenue of miners, blockchain performance in terms of stale block ratio and transactions per second, and blockchain security in terms of resistance against double-spending attacks. Numerical analysis is conducted to investigate the quantitative relationship between the relative-revenue-optimal mining strategy for malicious miners and two miner features in Bitcoin and Ethereum, respectively. The quantitative analysis results can assist honest miners in detecting whether there is any malicious miner in the system and setting the threshold of mining node's hash power in order to prevent malicious miners from making profit through selfish and stubborn mining.
Article
We investigate the impact on Bitcoin returns arising from cyberattacks on digital exchanges over the 2012 – 2021 period. In particular, we test the hypothesis that Bitcoin experiences lower returns on the dates associated with cybersecurity breaches of cryptocurrency exchanges. We find a negative and statistically significant impact where Bitcoin price declines by about 1.513 percent on the cyberattack days. However, a subsample analysis suggests that while the estimated effect is somewhat larger over the 2012 – 2018 period, it has lessened and become statistically insignificant in the more recent 2019 – 2021 subsample.