According to Foresight News, Paidun published a statement saying that Onyx appears to be a victim of a known precision issue in the forked CompoundV2 codebase. The vulnerability has been exploited by attackers to siphon off funds including 4.1 million VUSD, 7.35 million XCN, 5,000 DAI, 0.23 WBTC, and 50,000 USDT.