Summary

The isEligibleForReward function in the ScoreBoard contract determines if a player is eligible to receive a reward from the prize pool. However, it has a vulnerability due to an incorrect condition for eligibility, which contradicts the stated rules.

Vulnerability Details

https://github.com/Cyfrin/2024-07-the-predicter/blob/839bfa56fe0066e7f5610197a6b670c26a4c0879/src/ScoreBoard.sol#L94-L98

Issues Identified

1. Incorrect Eligibility Condition:

   • The function checks if predictionsCount is greater than 1, which requires players to have made at least 2 predictions to be eligible.

   • This contradicts the stated rule that players need to have paid at least one prediction fee and have a positive number of points.

Impact

Players who have made only one valid prediction and have a positive score may be unfairly excluded from receiving rewards. This can lead to player dissatisfaction and disputes, undermining the fairness and credibility of the tournament.

Tools Used

Manual review

Recommendations

The check playersPredictions[player].predictionsCount > 1 should be playersPredictions[player].predictionsCount > 0.