TechFlow News: On June 5, SlowMist issued a security alert stating that the DTXT/USDT trading pair on BSC was attacked due to forgeable logic for detecting liquidity additions. The attacker ultimately profited approximately $35,041.106 in USDT.
The root cause lies in DTXT’s method of determining whether an operation constitutes liquidity addition, liquidity removal, or token selling—by comparing USDT.balanceOf(pair) against the trading pair’s reserve difference. The attacker first directly transferred a negligible amount of USDT into the pair, causing a large-scale DTXT sell order to be misclassified as liquidity addition. This bypassed both the sell fee and the swapFee logic. Leveraging flash loans, the attacker then manipulated liquidity (adding and removing it), forged a 1-wei USDT balance, and directly called Pair.swap to drain USDT from the pair.
