A misconfiguration in the Ploutus protocol's oracle led to a significant loss of approximately $390,000 for a liquidity pool on Ethereum. The error involved incorrectly pegging the USDC price to Chainlink's BTC/USD price feed, resulting in a substantial price deviation. This allowed an attacker to exploit the situation by borrowing 187 ETH with just 8 USDC as collateral. The attack was executed immediately after the configuration change, suggesting the attacker was monitoring the update closely.