Bankroll Hack

On September 22, 2024, the DeFi protocol Bankroll Network was exploited, leading to a $230,000 loss due to a vulnerability in its token sale contract.

The attack focused on the "buyFor" function of the Bankroll Network’s token sale contract, which is designed to allow users to buy tokens for others by sending WBNB to a pool. However, the exploit allowed the hacker to manipulate the “profitPerShare_” variable by making the victim contract its own customer. This allowed the attacker to artificially inflate their share of the pool's profits without depositing the required WBNB.

After buying some tokens, the hacker repeatedly invoked the "buyFor" function hundreds of times, drastically increasing the "profitPerShare_." They then used the "withdraw" function to collect an oversized profit in WBNB, extracting $230,000 from the system. The attack likely used flash loans to make the initial deposit and trigger the manipulation.

Exploit tx:

https://bscscan.com/tx/0xd4c7c11c…4503b0