Submitted by WatchPug
The current design/implementation allows users who are refunded before to get another freeTrial. This can be exploited by malicious users to get an infinite free trial.
Given:
A malicious user can:
Repeat the steps above and the user can get infinite freeTrial.
A malicious third party may provide a service named freeUnlock, which will call cancelAndRefund() and purchase() automatically right before the end of the freeTrial. This can cause fund loss to all the owners that provide a freeTrial.
Consider adding a mapping(address => uint256) freeTrialEnds and make sure each address can only get 1 freeTrial.
julien51 (Unlock Protocol) disputed and commented:
0xleastwood (judge) commented:
julien51 (Unlock Protocol) commented:
0xleastwood (judge) decreased severity to Medium and commented:
