YO Protocol encountered a significant swap anomaly on Ethereum, where approximately $3.84 million worth of stkGHO was exchanged for just $122,000 in USDC. The incident, reported on January 13th, was analyzed by BlockSec, revealing that the issue stemmed from an incorrect estimated output value, which nullified slippage protection, and an abnormal transaction path through a high-fee, low-liquidity pool. This led to substantial fee extraction and price volatility. In response, the YO Protocol team has purchased GHO and re-deposited it into stkGHO to mitigate the impact.