Submitted by itsmeSTYJ
There is no sanity check to ensure that (primaryReserveRatio * _initialTokenSupply * _initialTokenPrice) is  (SCALE * 1e18). As a result, _primaryReserveBalance is given a value of 0 since divisions in solidity are rounded down. This also means that primaryReserveBalance and fictitiousPrimaryReserveBalance have a value of 0.
When this happens, the buy function doesnt work because _chargeFee will revert on line 222. You cant sell either since totalSupply == initialSupply. The only way to recover the NFT is for the owner of the NFT to call initiateBuyout but there is always the possibility that someone else also spotted this mistake and will attempt to also call initiateBuyout once the minBuyoutTime is reached. If the owner loses this gas war, the owner has effectively lost his NFT.
Add some sanity checks to ensure a sane expected value for _initialTokenSupply and _initialTokenPrice. There were multiple instances when a user tried to interact with a contract but entered a wrong value because they are not aware they needed to include decimals. A recent example of this is https://cointelegraph.com/news/1-million-rock-nft-sells-for-a-penny-in-all-ore-nothing-error.
Note: Normally, I would categorise issues like this as medium severity since it is a loss predicated on having met certain conditions but because there is also a lack of sanity check on _minBuyoutTime, it is entirely possible for a seller to lose his NFT immediately once the vault is created. There are many monsters waiting in the dark forest, all it takes is one mistake. That said, I will defer the final judgement to the judges & sponsors.
mundhrakeshav (Nibbl) disputed, disagreed with severity and commented:
HardlyDifficult (judge) commented:
HardlyDifficult (judge) decreased severity to Medium and commented:
