Blockchain networks are exposed to several security attacks, including selfish mining attacks, which occur when a miner or a group of miners withhold their newly mined blocks and keep them in their private chain rather than immediately broadcasting them to the rest of the network. This strategy forces honest miners to waste their resources and degrades the efficiency of the network. This paper introduces a novel game-theoretic approach leveraging a war of attrition framework to mitigate selfish mining in PoW blockchains. We design reward and punishment mechanisms to incentivize miners to opt for honest strategies and discourage them from choosing selfish tactics. Additionally, a reputation function is utilized to ensure that miners are not indifferent to the presence of selfish miners in the network. Moreover, we examine whether the honest strategy remains stable within the system using the evolutionary game theory. Our findings indicate that the honest strategy is indeed stable under the proposed model. Our solution will help mitigate the threat of selfish mining in blockchain systems.