It’s the same old problem of integer overflow—it really is written with a lot of confidence in this conversion logic.

According to ChainBBS news and SlowMist monitoring, the decentralized tipping protocol Drips Network was attacked, resulting in losses of about 24.9k DAI. SlowMist’s analysis shows that the root cause of the attack was an integer type conversion flaw in the give (address,uint128) function in the daidripshub contract. This function converts a uint128-typed amount to int128 without verifying whether the input parameter exceeds the maximum int128 value. By passing a specific value outside the int128 range, the attacker caused the converted amount to become negative, reversing the transfer direction. The reserve pool contract then executed abnormal withdrawals from its funds to the attacker’s account, ultimately exhausting the reserve funds.