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Ethereum is the world’s second-largest cryptocurrency
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Ethereum, the world’s second-largest cryptocurrency, slashed its energy use with a major change to how it works last year. Security experts say the update also unknowingly sidestepped a serious security flaw that could have allowed hackers to steal funds. However, at least one cryptocurrency that “forked” from Ethereum by copying its code is still at risk.
Ethereum used to rely on “proof of work” to secure its network, as bitcoin still does, meaning that computers performed huge numbers of calculations to “mine” new currency and …