Hash War: Mystery Miner’s Empty Block Attack Makes ABC’s New Blockchain Almost Unusable

According to various reports, the Bitcoin ABC pro-IFP chain has been under ‘attack’ for a number of consecutive days now. The mystery miner has been mining a great number of sequential blocks, but almost all of them have been empty. The miner who calls himself ‘Voluntarism.dev’ says the mining operation is a group of “old-guard miners,” and claims they can mess with the minority ABC chain for years.

‘The Price of Freedom Is Steep’

The cryptocurrency community has been watching the aftermath of the recent blockchain bifurcation, which saw the Bitcoin ABC node fork into its own blockchain. The Bitcoin ABC network is still nameless and without branding, and the token is often referred to as either “ABC,” “BCHA,” or “BAB.”

Last week, news.Bitcoin.com reported on a stealth miner who has been mining a large number of consecutive empty blocks. Because blocks have been empty for so long, it’s been hard for anyone to send a transaction on the ABC chain and get the transaction confirmed in a timely manner.

Since our newsdesk’s report, the mystery miner has introduced the group on Twitter under the account name Voluntarism.dev, and through coinbase parameter messages every time the pool finds an ABC block reward. On November 24, 2020, the Voluntarism.dev Twitter account created a message with a blockchain signature in order to verify its legitimacy.

The same day the miner tweeted: “good ideas don’t require force” and the following day the group tweeted a message to other miners pointing hashrate at the ABC chain. Voluntarism.dev said:

I hope all miners agree: we would like 100% of the BCHA coinbase reward to go to pqnqv9lt7e5vjyp0w88zf2af0l92l8rxdgnlxww9j9.

Later on that day, the pool tweeted that “the price of freedom is steep” and also tweeted some screenshots of Bitcoin ABC’s lead developer Amaury Séchet discussing the infrastructure funding plan (IFP).

“ABC violated the (non-aggression principle) NAP with 9 months of civil war,” the Voluntarism.dev Twitter account stressed in another tweet. “Freeriders must pay 100% of the block reward to ABC. We will orphan all blocks that do not. We will pay 100% as well, once ABC merges this change,” the pool added.

In another statement Voluntarism.dev said:

The amount of value that ABC stole from [Bitcoin Cash] pales in comparison to our expenditures. We are a group of old-guard miners and whales. We can do this for years. Next time you fork: use your own genesis block, your own PoW [algorithm], and build your own community. [Bitcoin Cash] is protected.

Meanwhile, between Thursday and Saturday, it took more than 24 hours before any ABC pro-IFP transactions cleared, and the blockchain has suffered a total of two blockchain reorganizations (reorg) to-date. This means after a block has been mined by a miner other than Voluntarism.dev, it’s been reverted and the once confirmed blocks simply disappear. On Saturday morning, there was an attempt to reorg the ABC chain a third time, but it was reverted by the pool Mining Dutch. The mining pool Mining Dutch has managed to process thousands of transactions for senders on Saturday early afternoon (EST).

@yhaiyang idea for you. dump your BCHA holdings into your own customer buy walls, then make it worth $0 (per your risk warning) https://t.co/ZFHg17KDZz pic.twitter.com/dVFy4m4rWG

— voluntarism.dev (@DevVoluntarism) November 27, 2020

Spawn Camp Attack or Enforced Consensus Mechanism?

On November 28, 2020, the cofounder of Ethereum, Vitalik Buterin tweeted about the mystery mining pool that controls 90% of the ABC chain’s hashpower today. “ [A] mining pool 51% attacks BCHA seemingly with the explicit goal of destroying it. Will this be the first true spawn camp attack on a PoW chain?” Buterin asked his Twitter followers.

However, the recent empty block attacker is not the first true spawn camp attack on a PoW chain. A Bitcoin clone called Coiledcoin appeared in 2012 and it has been said that it was also attacked by hashrate. The BTC community accused the Core developer, Luke Dash Jr., of leveraging the mining pool Eligius in order to takedown the Coiledcoin project. Software developer Peter Todd spoke about the event on Twitter in 2016 when ethereum classic (ETC) was threatened by a 51% attack.

On Friday, in a reply to Buterin’s tweet about the mystery miner, BCH proponent, and researcher, Javier González explained that the mining pool’s technique was not an attack. “It is not an attack, it is defensive,” González said. “Bitcoin ABC has fractured the BCH project to capture 8% of the coinbase miners incentive. 90% of the BCH [hashpower] voted against it. And now they are defending their interests. Enforced consensus mechanism,” González insisted.

News.Bitcoin.com spoke with González on Saturday, while the third blockchain reorg attempt took place. González is also the inventor of the Bitcoin Mining Parliament (BMP), a concept that confronts Bitcoin Cash network issues using Nakamoto Consensus.

During the morning hours (EST), the mining pools Viabtc and Mining Dutch mined blocks 662396 and 662397. Both of these blocks confirmed thousands of transactions, but again, Voluntarism.dev reorganized the chain with its massive hashpower and the blocks disappeared. González sources data from the block explorer Blockchair and also runs his own ABC pro-IFP node. Although not too long after, confrontational hashpower was able to stop Voluntarism.dev’s third reorg attempt.

“The first empty block + reorg attack to destroy a minority split attempt (BAB/BCHA/ABC) is occurring,” González told news.Bitcoin.com on Saturday. “I think they are a group of miners and BCH whales that are acting in coordination to defend the [Bitcoin Cash] blockchain from the split caused by Bitcoin ABC (Amaury) to capture the 8% of the coinbase incentive that belongs to the miners. González further added:

Basically, Amaury believes it has the right to break up the project and take the 8% (who knows how much in the future). But that is being denied by hashwar.

Mystery Miner’s Third Attempt to Reorg ABC Met With Confrontational Hashpower

González also said that the ABC chain only has two mitigations; either selectively ignore hashpower (total centrality) or change the algorithm in emergency. The researcher further highlighted that the ABC chain has no use and that markets may have to delist the coin. While the mystery miner empties blocks it is also optimizing the assault by making it cheaper González detailed.

“What we are seeing is what I call ‘executive mining.’ That is, it is not ‘automatic mining’ following the market incentive, but the miners are following their own brains, spending money, thinking of a bigger future incentive (in this case, it seems to be the defense of BCH),” González emphasized.

While conversing with the researcher another two blocks were mined by the pool Mining Dutch. González said that the mystery miner Voluntarism.dev is now being confronted in the hash war. “A large amount of hashrate has reversed the reorg, protecting BAB,” González detailed. Currently, there have been two successful reorganizations and one failed attempt on Saturday morning.

After the two blocks were found by Mining Dutch, Voluntarism.dev mined four blocks after that, the pool said the confrontational hashpower was a “bully” in the following coinbase message. Following the four blocks mined by Voluntarism.dev (662412, 662413, 662414, 662415), Mining Dutch got another two blocks and managed to process transactions.

As of right now, BCH supporters and ABC proponents will be watching the chain with their eyes peeled. So far, it seems the chain is far from functional and the network’s existence going forward is uncertain.

What do you think about the hash war and the mystery miner? Let us know what you think about this subject in the comments section below.

Image Credits: Shutterstock, Pixabay, Wiki Commons, Charts by Javier González, Coin Dance Cash ABC hashrate distribution,