An Investigation and Analysis of Vulnerabilities Surrounding Cryptocurrencies and Blockchain Technology

As individuals search for a safe and alternative payment method, the popularity of cryptocurrencies and blockchain technology continues to grow. Despite their benefits, the increasing prevalence of these technologies also exposes them to a higher risk of encountering potential threats. These threats stem from the vulnerabilities and technical limitations within, which in turn, influences its potential to be adopted across different industries. Through a quantitative approach, this paper aims to detect and mitigate the vulnerabilities and technical limitations within cryptocurrencies and blockchain. Bitcoin was chosen because of its established reputation and widespread recognition in the market. A simulated environment provides the means to study distinct parameters within a Bitcoin network, particularly in the event of a double-spending and selfish mining attack. Based on the findings, the success rate and revenue of the attacker were primarily influenced by the network’s stale block rate, the attacker’s hash rate, and the double-spend value. Moreover, there is a significant difference in the parameters pre- and post-attacks. The block size has a considerable effect on the parameters in the network. As such, a single-objective problem is solved to determine what the optimal block size should be to minimize the block generation time and block delay time, seeking to reduce the overall latency and increase the throughput. It can be concluded that using the optimal block size can partially reduce the threat of double-spending attacks, but not eliminate it. It becomes evident that other mitigation schemes should be implemented to overcome these vulnerabilities.