Pentagon-commissioned report claims just 4 entities can disrupt Bitcoin
Investigation by security experts Bit trajectory We conclude that the concept of blockchain decentralization is wrong. In particular, the report argued that controlling the four largest mining pools could disrupt the Bitcoin chain, and Ethereum could be even worse with three entities.
“”Number of entities suffiThe ability to break the blockchain is relatively low: four For Bitcoin, 2 for Ethereum, less than 12 for most PoS networks. “
This report was commissioned by the Defense Advanced Research Projects Agency (DARPA), a research and development division of the Department of Defense. mission By investigating techniques for potential military applications.
According to the website Tech RepublicTargeted at IT professionals, this report raises further questions about blockchain technology when security risks and crypto price instability are at the forefront of everyone’s mind.
“DARPA’s consignment report only adds to the concerns about blockchain and impacts investor perception and confidence.”
Blockchain is not immutable
The report details immutability, the Nakamoto factor, which represents the number of entities required to successfully attack a network, mining pool vulnerabilities, 51% attack, network topology, and network and software centrality. increase.
The most important findings show that immutability can be broken, and distributed ledger technology (DLT) is through reliable, consensus, motivational, topology, network, and software means. It can be centralized.
Further expanding, the report states that virtual machines (VMs) used to incorporate new features and perform security migrations are potential gateways to break immutability.
“”Bitcoin and its derivatives A VM for interpreting transaction output scripts.Ethereum uses VM Smart contract. “
Software authors and maintainers may “change blockchain semantics” through VMs. This includes returning the blockchain to its previous state. The Trail of Bits shows an example of an Ethereum developer doing this in response to a 2016 DAO attack.
“Every blockchain has a privilege set of entities that can change the semantics of. Blockchain that may change past transactions.. “
Therefore, neither blockchain data nor code can be considered “meaningless”.
Bitcoin is centralized
Although blockchain is marketed with the concept of operating safely without centralized control, researchers say that DLT can be centralized in several ways.
Bitcoin’s Nakamoto coefficient is 4. In other words, you can attack your network simply by controlling four mining pools. The closer the coefficient is to 1, the more centralized it is.
“Bitcoin Nakamoto Co.fficient is 4, This is because controlling the four largest mining pools provides a hash rate su.fficient Performs 51% of attacks. January 2021, Nakamoto KoffiEthereum cient Only two.12 As of April 2022, there are three. “
While the cost of controlling four Bitcoin mining pools is uneconomically high, Trail of Bits researchers say unfriendly people who have the resources to thwart competing chains and such attacks. It claims that there are still “reverse incentives” from the state and others.
Other important findings include that more than one-fifth of Bitcoin nodes are running older client versions with known vulnerabilities. And 60% of all BTC traffic goes through three internet service providers.
