Majority is not Needed: A Counterstrategy to Selfish Mining

In recent years, several works have investigated selfish mining attacks, where a miner or group of miners withhold blocks to gain an advantage over honest miners. Most of these studies assumed that miners outside the selfish mining pool would continue to mine honestly. However, remaining honest is typically not incentive-compatible, especially if another pool is using selfish mining or a similar strategy. In this paper, we reveal the opportunity for a sufficiently large pool to exploit another selfish mining pool, enabling it to monopolize profits and launch 51% attacks with less than half the total computing power. We show that beyond selfish mining, this strategy can leverage any approach that deviates from honest mining.