All altcoins may be vulnerable to a 51% attack, experts believe. As crypto coins become mainstream, there are plenty of low-hashrate coins with a high public profile. Verge (XVG) is one of the more prominent examples, but there are other potential targets. Some go as far as to suggest even Bitcoin can, in theory, be attacked, and that Bitmain has the hashing power to achieve that feat.
https://twitter.com/ArminVanBitcoin/status/1000228244539478016
In theory, even the remotest possibility for a malicious rollback of transactions could “kill” a coin, wiping out its credibility. But in the past, miners with significant hashing power have not acted maliciously. One of the most egregious examples was the early mining of Bitcoin Cash (BCH), where a single Unknown entity, possibly Bitmain, solved most blocks.
Other recent victims of a 51% attack include Bitcoin Gold (BTG), where a concerted effort to double-spend transactions bound for exchanges undermined trust in the network. The BTG team notified exchanges, asking them to wait for more verifications, up to 21 confirmations of a transaction. But the attack, noticed this May 15, may have stolen up to $18 millions’ worth of coins. The attacker sent coins to an exchange, sold them for BTC or other assets, and withdrew them - then forced the network to reverse the initial transaction to the exchange.
Estimates see up to 380,000 BTG coins involved in double-spending behaviors, although it is unknown how many were successfully sold.
But there are many more small coins where a 51% attack may happen at any moment, if more hashing power is pointed at them before difficulty adjusts:
https://twitter.com/CobraBitcoin/status/1000063690538934272
In another example of blockchain vulnerability, Mona Coin (MONA) saw trouble with block production, in what experts believe was a 51% attack. The MONA attack used a bug that allowed the withholding of blocks, followed by block timestamp exploit. For now, exchanges are asking for more than 100 confirmations to avoid losses from selling double-spent coins.
Curiously, MONA is at peak prices against BTC, at 4,618 Satoshi, despite the dollar price of $3.40. Other coins have fallen more on general market pessimism, not necessarily due to the attack. Verge (XVG) dropped as low as $0.037, while Bitcoin Gold (BTG) slid to $42.23.
For now, some of the leading crypto coins are mostly protected, due to the expense of an outright attack. However, there is the scenario where hashing power consolidates, or there is a cartel, or a hidden miner of more than 51% of the hashing power - a feat quite possible in a world where mining is an arms race of powerful ASIC machines.
https://twitter.com/sassal0x/status/1000948257554509824
The chief reason for the hashing power attacks is the presence of already large pools of mining tools available for all types of algorithms. Pointing that hashing power to one coin can achieve similar behaviors, where exchanges may bear the brunt of losses.
Coins most threatened are the ones using algorithms that are mined by large entities, including SHA-256, Scrypt, and Equihash. The leading coins with those algorithms are safe, but clones and forks with smaller mining rate and difficult are vulnerable.
This article appeared first on Cryptovest
