Submitted by 0xNineDec, also found by thecatking
https://github.com/code-423n4/2023-01-popcorn/blob/d95fc31449c260901811196d617366d6352258cd/src/vault/Vault.sol#L151-L153 
https://github.com/code-423n4/2023-01-popcorn/blob/d95fc31449c260901811196d617366d6352258cd/src/vault/Vault.sol#L480-L491 
https://github.com/code-423n4/2023-01-popcorn/blob/d95fc31449c260901811196d617366d6352258cd/src/vault/Vault.sol#L594-L613
Vaults using hookable tokens present a reentrancy upon changing adapter. Each vault has the takeFees() modifier that processes performance and management fees. That modifier is invoked only in two opportunities: 
takeManagementAndPerformanceFees() (external non access controlled) and when changing an adapter with changeAdapter() (external, non access controlled and depends on having a previously proposed adapter).
The takeFees() modifier consumes from the totalAssets() balance to calculate the amount of management fees via accruedManagementFee():
However, a vault using hookable tokens can perform a reentrancy if the following conditions are met:
This reentrancy will be triggered by a hook called before the safeTransferFrom() upon deposit() and the instructions performed inside that hook will occur after _mint() and before the assets are effectively transferred to the vault:
The hookable token can call changeAdapter() in a before transfer hook and the contract will use outdated balance values. This is because the vault increases the amount of shares before capturing the assets.
A vault with a hookable token is deployed by Alice. The used token allows users to create custom hooks that run before and/or after each call. A change of adapter is enqueued.
Output:
With the deposit and current amount of shares used for the PoC, it can be seen how the reentrant call yields in a total of 7.119e16 minted shares whereas a normal non-reentrant flow mints 1.06e17. This means that 33% of the fees are not transferred to the recipient.
The output was built by adding console logs inside each relevant Vaults function. To reproduce both non reentrant and reentrant scenarios comment the token hook and the respective parts of the PoC.
Consider adding the nonReentrant modifier to the changeAdapter() function.
RedVeil (Popcorn) acknowledged, but disagreed with severity 
LSDan (judge) decreased severity to Medium 
