Discussion on Bitcoin's Technical Flaws and Possibility of Cracking

Bitcoin, as a digital currency that subverts the traditional financial system, has attracted the attention of global investors and technology enthusiasts since its launch in 2009. Its decentralization, anonymity and immutability make it the "digital gold" in the minds of many people. However, with the gradual popularization and application of Bitcoin, the problems of its technical flaws and security are becoming increasingly apparent. This article will explore the technical flaws of Bitcoin from multiple perspectives and whether it is possible to be cracked.

The core technology of Bitcoin is based on blockchain, a distributed ledger technology. Each transaction is recorded in a block and verified and linked through complex mathematical algorithms. Although this structure ensures the security and transparency of data, in actual applications, the technical flaws of blockchain have gradually surfaced. For example, the delay in transaction confirmation time and network congestion problems, especially when the price of Bitcoin soars, users often have to wait for a long time to complete the transaction. In this case, the user experience is obviously affected.

In addition, the scalability of blockchain is also a major challenge facing Bitcoin. The transaction throughput of the Bitcoin network is relatively low, and can only process about 7 transactions per second. This figure is far lower than the ability of traditional payment systems such as Visa to process thousands of transactions per second. Therefore, when the network is overloaded, transaction fees will soar, and users need to pay higher mining fees to speed up transaction confirmation. This phenomenon not only affects the effectiveness of Bitcoin as a means of payment, but also makes its function as a store of value questionable.

In terms of security, although Bitcoin's encryption algorithm is considered very secure, it does not mean that it is completely unbreakable. With the continuous development of computer technology, especially the rise of quantum computing, many experts have begun to worry that the security of Bitcoin may be threatened. Quantum computers can solve complex mathematical problems in a short time that traditional computers take a long time to complete, which may make Bitcoin's encryption mechanism vulnerable. Although quantum computing is still in the experimental stage, its potential threat cannot be ignored.

Bitcoin's technical defects are also reflected in its governance mechanism. The decision-making process of the Bitcoin network is very slow, and any major changes require broad consensus. Although this decentralized governance has enhanced security to a certain extent, it is extremely slow in responding to technological updates and network upgrades. In 2016, the dispute over Bitcoin's block size triggered a fierce fork, which eventually led to the birth of Bitcoin Cash (BCH). This incident not only revealed the fragility of Bitcoin governance, but also made people think deeply about its future development direction.

Although Bitcoin's technical flaws have sparked widespread discussion, its value as an emerging asset cannot be underestimated. Many investors remain confident in Bitcoin and believe that its potential is far from being fully tapped. Bitcoin's decentralized nature makes it not controlled by any government or financial institution, which is particularly important in the context of economic instability or increased geopolitical risks. To some extent, Bitcoin is seen as a "safe haven asset" that attracts a large number of investors seeking to preserve their assets.

However, while investors are paying attention to Bitcoin, they must also be aware of its potential risks. The Bitcoin market is extremely volatile, and prices may fluctuate dramatically in a short period of time, which brings great psychological pressure and financial risks to investors. In 2017, the price of Bitcoin soared from about $1,000 to nearly $20,000, and then quickly fell to around $3,000 in 2018. This trend caught many investors off guard. Therefore, it is particularly important to invest rationally and analyze market dynamics scientifically.

In the face of Bitcoin's technical flaws and security issues, many experts have called for further technological innovation and improvement. For example, the Lightning Network, as a second-layer solution, aims to solve the delays and fees of Bitcoin transactions. It significantly improves the speed and efficiency of transactions by conducting transactions off-chain. In addition, many developers are studying how to introduce quantum-safe algorithms into the Bitcoin network to cope with possible quantum computing threats in the future.

The future of Bitcoin is still full of uncertainty, but its influence has profoundly changed people's perception of currency and finance. Both technical defects and security concerns provide opportunities for reflection and improvement in the development of Bitcoin. As investors, we need to keep an open mind and pay attention to technological progress and market changes in order to seize opportunities in this rapidly changing field.

In summary, as an emerging digital currency, Bitcoin, despite its technical defects and security risks, its potential value and influence cannot be underestimated. With the continuous evolution of technology and the maturity of the market, the future of Bitcoin is still full of hope. While paying attention to its defects, we need to actively think about how to promote technological innovation to achieve wider application and higher security of Bitcoin. Only in this way can we find a path to sustainable development in this challenging era of digital currency.

The four most famous international exchanges:

Binance INTL	OKX INTL	Gate.io INTL	Huobi INTL
China Line　APP DL	China Line　APP DL	China Line　APP DL	China Line　APP DL

Note: The above exchange logo is the official website registration link, and the text is the APP download link.

Does Bitcoin have technical flaws? Will Bitcoin be cracked? [Technews Technology News] Recently, an independent information security researcher Sergio Demian Lerner published an article pointing out the possibility of cracking Bitcoin, which caused a lot of controversy. The article stated that there are ways to reduce the security of SPV. I later discovered that he was not the first person to know about this vulnerability. Several core teams that operated Bitcoin in the early days may have known about this information. There are flaws in the design of Bitcoin's Merkle Tree, which can deceive victims who use SPV wallets. SPV is called Simple Payment Verification, which was mentioned in the earliest white paper of Satoshi Nakamoto. Its goal is to exempt users from running the entire blockchain. After all, the blockchain is getting longer and longer, which will hinder transactions, and SPV technology exempts users from verifying the full node blockchain. When using SPV, as long as it is determined that a transaction has appeared in a block on the main chain, it can be proved that the transaction has been verified before. In order to achieve such a judgment, it is necessary to search through the Merkle tree. The key point is that Bitcoin's Merkle tree does not distinguish between internal nodes and leaf nodes, and the depth of the entire tree is determined by the number of transactions. However, the node does not have a specific format, as long as it meets the length of 64 bits, so the attacker can deceive the victim's wallet by submitting enough transaction information and letting the victim's system retranslate it into a transaction, and complete any number of transactions out of thin air.

Merkle tree containing fake transaction blocks. (Source: Sergio Demian Lerner's Blog)

Of course, it is not easy to exploit this vulnerability. It requires running 69 to 73 bits of brute force, and each operation must face the SHA-2 cryptographic hash function calculation, and the SPV
wallet itself has a simple probabilistic protection mechanism. Even the example given by the author cannot be applied to platforms such as coinbase, which requires brute force cracking up to 216 bits, which is almost impossible at present.

Moreover, it is still very expensive to execute this transaction for SPV wallets. First of all, it may be necessary to customize ASIC. Although it is similar to the design of current miners, it is estimated that it will cost nearly 1.3 million US dollars to meet the computing power requirements. Depending on the node density, its design cost may be increased by nearly one million. In addition, in order to prevent other miners from reorganizing the blockchain, additional costs may be required, which makes it necessary to defraud millions of dollars to be profitable.

Although the attack method I proposed is definitely not the best, when conducting large-scale Bitcoin transactions, it is usually verified as a whole instead of using simple SPV. In addition, if the SPV wallet is required to perform special self-checks, there is a high chance that abnormal transactions will be discovered. Therefore, this vulnerability is probably still only in theory. However, in special circumstances, this attack can be made cheaper, such as if the attacker happens to hold a suitable node, so the possibility of the vulnerability must still be explored.

I have also proposed some solutions to this problem, and I hope it will be more widely discussed. Of course, some people responded that it would take too many coincidences to meet the conditions revealed by the author, and some even said that compared with the harm of brute force cracking to the blockchain, the manipulation of a few people and the crazy ICO are the real problems. However, this article has indeed attracted a lot of attention in this circle.