Submitted by johnnycash, also found by WatchPug, csanuragjain, gpersoon, gzeon, harleythedog, kemmio, kenzo, leastwood, and pauliax
It allows an attacker to retrieve all the tokens of each promotions.
Anyone can create a new promotion using createPromotion(). An attacker can create a new malicious promotion with the following parameters:
The only verification made on the ticket address given by _requireTicket() is that the smart contract must implement the ITicket interface.
The attacker can then call claimRewards() with its wallet address, the malicious promotion id and a single _epochId for the sake of clarity.
The attacker receives the tokens of other promotions without having spent anything.
The malicious smart contract is a copy/paste of TicketHarness.sol and Ticket.sol with the following changes:
The test for HardHat is:
It results in the following error:
Maybe add a whitelist of trusted tickets?
PierrickGT (PoolTogether) confirmed 
