Unnecessary payable attribute may allow users to send/lock BNB accidentally

[code423n4]

Handle

0xRajeev

Vulnerability details

Impact

The payable attribute will allow swapTo() to receive BNB and may confuse/allow users into sending BNB to contract trying to swap that to token, which is not the case. This will lead to user's BNB getting locked in this contract without a way to retrieve it.

Proof of Concept

https://github.com/code-423n4/2021-07-spartan/blob/e2555aab44d9760fdd640df9095b7235b70f035e/contracts/Pool.sol#L210-L226

Tools Used

Manual Analysis

Recommended Mitigation Steps

Remove payable attribute as it is not required here.

[SamusElderg]

Duplicate of #46