Summary

Weak randomness because of msg.sender, block.timestamp, and block.prerandao hash.

Vulnerability Details

Hashing msg.sender, block.timestamp, and block.prerandao together creates a predictable number. Malicious users can manipulate
these values or know them ahead of time to choose the winner of the raffle themselves

Validators can influence block.timestamp

Impact

Any user can influence the winner of the battle, and winning the money.

Tools Used

Recommendations

Consider using a cryptographically provable random number generator such as Chainlink VRF and do not use block.timestamp