Ethereum’s prowess is theoretically challenging its rival – currently standing ETH is enough to carry a 51% attack on Bitcoin Network. Around 2 Million ETH worth $3.6 Million is considerable enough to acquire the necessary Bitcoin to perform the attack.
Ether Could Be Used to Perform a 51% attack on Bitcoin Network
It is known that Ethereum and Bitcoin are two different blockchains working on different consensus mechanisms. Hence Ethereum can not be directly used to influence the operations of the Bitcoin network. Also, this is just a theoretical assumption.
A 51% attack occurs when a single entity gains control over more than half of the blockchain’s mining power or hash rate. Such a scenario would allow the attacker to manipulate the transactions and double-spend coins to the heart’s content.
As the Bitcoin network works on Proof-of-Work (PoW) consensus mechanism, it is technically vulnerable to such an attack.
Also, the fundamental goal of a blockchain is to ensure security, transparency and trust amongst its users. A 51% attack completely contradicts this concept and could be catastrophic for the network’s value, trust and reputation.
Even though the accumulation of Ether waiting to secure the Ethereum Network is praiseworthy. The possibility that it can be used to carry out a 51% attack on the Bitcoin Network is just a hypothesis and far from reality.
What is a 51% attack, anyway?
If a group of miners gain control over 50% of the mining hash rate and own 51% of nodes, they would attain the controlling power of the blockchain. The group would then introduce a different blockchain network, which has to enter the network at a particular time before forming the next block. The network should accept this blockchain, which it theoretically would do as the attacker owns most of it.
However, transactions should be stopped before the attack starts to change historical blocks. This process would be complicated to carry out, as the further back the transactions are, it becomes problematic to change them. If they manage the impossible and change transactions before a checkpoint, the new blockchain becomes a permanent part of the network.
Also, the cost to carry out such an attack is larger than the reward. First, the group has to out-hash the leading network and insert a newly created blockchain at the precise time.
If any group wished to perform a 51% attack on the Bitcoin network, they would have to surpass the hash rate of the three biggest mining pools combined. FoundryUSA, AntPool and Binance Pool have a united hash rate of 130.4 EH/s. To reach this number, attackers would need more than 511,373 S19 XP Hydros mining equipment, which alone would cost around $10.13 Billion. Also, hosting, maintenance and cooling costs will be added.
This cost of acquiring the required hash power discourages an attacker from performing a 51% attack on the Bitcoin network.
In the case of Ethereum or any Proof-of-Stake (PoS) blockchain, gaining access to 51% of the staked assets would give the power to own the network. As per the current data, around 13.8 Million ETH were staked by September 2022. If anyone decided to own 51% of Ethereum, they had to hold more than 6.9 Million ETH, worth only $12.4 Billion.
Even if someone has this amount lying around and decides to perform the attack, the consensus mechanism would recognize it and immediately destroy the staked ETH. This means that all the amount spent would be in vain. Moreover, the Ethereum community could vote to restore the honest chain; this way, the attacker would lose all ETHs and see the damages being repaired.
Source: https://www.thecoinrepublic.com/2023/05/21/enough-eth-in-queue-to-carry-out-51-attack-on-bitcoin-network/