Privacy-focused cryptocurrency, Grin is undergoing a 51 percent attack on its blockchain as an unknown miner gained control of more than 50 percent of its mining hash rate.
A notice published at the bottom of Grin’s website warns its community of the attack and urge them even to wait for ‘extra confirmations’.
“The Grin network hashrate has increased considerably over a short period of time. Notably, this coincides with the nice hashrate doubling in this time with well over 50% of the network hashrate currently outside of known pools,” Grin noted. “Considering these circumstances it is wise to wait for extra confirmations on transactions for payment finality.”
A Classic Way to Attack Any Blockchain
In a , the attacker gains over 50 percent of the blockchain’s total hashrate and thus can make many compromising changes to the network. This one is one of the widely used tactics in the early blockchain attacks. Though networks are now taking precautions, many are still vulnerable to such attacks.
2miners.com, which is Grin’s top miner with around 19.1 percent of the network hash power, pointed out the unknown miner on Saturday that has gained significant control of the blockchain network.
Grin Network Is Under the 51% Attack!
Payouts are stopped. Please mine at your own risk only because the new blocks could be rejected.
— 2Miners (@pool2miners)
Though initially, the suspicious miner accumulated 57.4 percent of the total Grin hash power, now its stake increased to 58.1 percent, according to Grinscan. Though the intentions of the suspicious miner are still unknown, it reorganized at least one forked block.
Since Saturday, the control of Grin hashrate by 2miners.com also increased to 24.5 percent, while Spartpool stands next with 11.4 percent.
Launched in January 2019, Grin is one of the few cryptocurrencies based on the protocol. The blockchain later that year to block the possibility of mining the coin with ASIC, along with the integration of a ‘bulletproof rewind scheme’ for its wallets.
Meanwhile, many other blockchains, including and , suffered such 51 percent attacks multiple times.