Altcoin News: Bitcoin Cash (BCH) Has Suffered from a 51% Attack from 2 Miners Only
May 24, 2019, by Marko Vidrih on ALTCOIN MAGAZINE
Only 9 days after Bitcoin Cash (BCH) update with the help of hard fork which, however, indicated that there are certain technical problems in the updated chain, BCH is under attack again — this time 51% attack.
The recent double attack on Bitcoin Cash right after the fork (poisonous transactions causing empty blocks to be mined by exploiting a bug in the code, and the intended theft of all coins locked in SegWit addresses by an (unknown miner) has been prevented by an alleged collaboration of two BCH mining pools who orphaned the theft block of the unknown miner. In the confusion, an unknown miner tried to snatch a bunch of P2SH/Segwit coins. But BTC.TOP and BTC.COM were expecting, and/or preparing to recover SegWit coins themselves.
The alleged attacker has sent out a private message to various community members spreading fear by accusing BCH to be centralized and being a victim of a 51% reorg attack by BTC.top and BTC.com. When the unknown miner tried to take the coins themselves, BTC.TOP and BTC.COM saw and immediately decided to re-org and remove these TXs, in favor of their own TXs, spending the same P2SH coins, plus many others.
A couple of hours ago Guy Swann tweeted that
The Twitter thread points to two resources BTC.TOP and BTC.com and r/btc also contain several discussion threads. Currently, miners have majority hashpower and they can use it to censor transactions, THIS IS A 51% ATTACK.
We can also see that on Reddit moderators of subreddit r/btc set comments thread to 0 points to censor the dissent. Perhaps some of the comments are also deleted.
Long story short writes one of the Reddit users:
- Miners BTC.TOP and BTC.com decided to prevent the appropriation of segwit coins for which keys had been exposed in the BTC [BCH] chain.
- A smaller miner tried to collect all those coins. Some person (either independently or in coordination with the miner) exploited a bug in Bitcoin ABC which prevented miners running Bitcoin ABC from creating new blocks.
- The Bitcoin ABC team released a patch. Miners upgraded and BTC.top proceeded with the plan.
- An unknown miner mined a block appropriating many SegWit coins.
- Prohashing mined a block on top of the unknown miner.
- BTC.top orphaned the two blocks.
- Prohashing team complained.
- Most discussions were about.
- The reality that the majority of the power uses Bitcoin ABC and the risk it represents:
-If the person exploiting the bug was a gray or black hat working with the unknown miner.
- If it was morally correct or not for a miner to take that action.
- If enabling SegWit recovery had been properly planned.
It appears that 2 miners were ready and communicating with each other directly and possibly another party (exchange or devs) for coordinating the re-org. Block reorgs seem to be a hot topic lately and were successfully pulled off by BCH miners.
“So just 2 miners, in secret & w/ no trouble, took it upon themselves to remove 2 blocks w/ another’s TXs, & replace with their own. Bizarrely, some are celebrating! Some devs are quiet, but jtoomim (#BCH dev) called it “justice,” & “punishment” for “antisocial behavior,””
— writes Swann.
Some of the Twitter users pointed out that attack was coordinated by BCH team. Perhaps to prevent a miner to exploit a bug. It seems that they are attacking their network to protect it.
This is what everyone warned about endless HFs. Its an attack vector which has turned BCH into a political mess where private community control what does/doesn’t get in a block.
“There are at least a few people (maybe only partially) realizing that this basically kills any perception that BCH is “decentralized, censorship-resistant money.” And leaves them to fight over whether the miners are “good guys” or “bad guys” with their actions,”
— Swann added in the tweet.
Author: Marko Vidrih
