THE FEATURE Blockchain's Once-Feared 51% Attack Is Now Becoming Regular Monacoin, bitcoin gold, zencash, verge and now, litecoin cash. At least five cryptocurrencies have recently been hit with an attack that used to be more theoretical than actual, all in the last month. In each case, attackers have been able to amass enough computing power to compromise these smaller networks, rearrange their transactions and abscond with millions of dollars. More surprising, though, may be that so-called 51% attacks are a well-known and dangerous cryptocurrency attack vector. While there have been some instances of such attacks working successfully in the past, they've been so rare, some technologists have gone as far as to argue miners on certain larger blockchains would never fall victim to one. The age-old (in crypto time) argument? It's too costly and they wouldn't get all that much money out of it.
But that doesn't seem to be the case anymore. | 
