First Flight #2: Puppy Raffle

Summary

The getActivePlayerIndex function in the provided smart contract incorrectly handles non-existing player queries by returning a default index value (0) that could correspond to a valid player, potentially leading to incorrect data interpretation or manipulation.

Vulnerability Details

In the getActivePlayerIndex function, when a non-existing player's address is queried, the function defaults to returning 0. This is problematic because index 0 could be a valid index for an existing player in the players array. This behavior can lead to ambiguity and incorrect information being returned, affecting the contract's logic relying on this function.

Impact

• Data Misinterpretation: Functions or external contracts relying on getActivePlayerIndex might incorrectly assume that a non-existing player is the first player in the list.

• Potential Logic Errors: Contract logic that uses this function's output could behave unpredictably or incorrectly.

• Manipulation Risk: Malicious actors might exploit this flaw to influence contract behavior, assuming specific actions are tied to the player at index 0.

Tools Used

manual

Recommendations

• Distinct Return Value for Non-Existence: Modify the function to return a distinct value (such as the array length or a special flag) when the player is not found.

• Use a Mapping: Consider using a mapping for player existence checks if applicable.

• Explicit Error Handling: Alternatively, the function could revert with an error message when the queried player does not exist.