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ut some risks posed by cryptoassets are new: oracles (which supply smart contracts with off-chain information such as asset prices), smart contracts and custodians are all vulnerable to hacks, which could undermine confidence. Confidence could also be undermined by issues with the blockchain settlement layer (eg Ethereum), including: miners extracting rents by front-running transactions, and high transaction fees and validator concentration, which can enable malicious behaviour in how new blocks are added to the blockchain.
From Cryptoassets, the metaverse and systemic risk – Bank Underground:
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