It assumes totalAssets and totalShares cannot be 0. This could happen if the contract is just initialized.

Summary

In the convertToShares and convertToAssets functions, it is possible for _totalAssets or _totalShares to be 0 if the contract was just initialized.

Vulnerability Detail

the convertToShares() and convertToAssets() functions could divide by 0 if _totalAssets or _totalShares is 0. Here is the relevant code: Link1 and link2 If _totalAssets or _totalShares is 0, it would cause a division by 0 error and revert the transaction.

This could happen right after deploying the contract, before any assets or shares have been minted. Or if assets and shares have been burned down to 0 for some reason.

An attacker could intentionally manipulate assets and shares to 0 to make the contract unusable.

Impact

An attacker could intentionally manipulate assets and shares to 0 to make the contract unusable.

Code Snippet

https://github.com/sherlock-audit/2023-09-perennial/blob/main/perennial-v2/packages/perennial-vault/contracts/Vault.sol#L130-L134 https://github.com/sherlock-audit/2023-09-perennial/blob/main/perennial-v2/packages/perennial-vault/contracts/Vault.sol#L139-L143

Tool used

Manual Review

Recommendation

The contract should check for 0 values and handle them safely

sherlock-audit / 2023-09-perennial-judging

feelereth - It assumes totalAssets and totalShares cannot be 0. This could happen if the contract is just initialized. #50