Once hailed as unhackable, blockchains are now getting hacked

By Stephen Downes - Stephen's Web. Once hailed as unhackable, blockchains are now getting hacked
Mike Orcutt, MIT Technology Review, 2019/02/21
One of my colleagues, Andriy Drozdyuk, has been saying all along that there is only one real blockchain, Bitcoin, because the innovation is as much social as it is technical. It is the investment and number of distinct users that makes it secure, not the technology. The recent Ethereum Classic hack may be proving him right. In this hack, bad actors took over more than half of the nodes and then began to write 'double spend' transactions, effectively defrauding the system. Ths is th sort of attack blockchain technology - though not necessarily Bitcoin - is vulnerable to. More...