_DOMAIN_SEPARATOR is not updated, when name of token is changed

[c4-submissions]

Lines of code

https://github.com/code-423n4/2023-09-centrifuge/blob/main/src/token/ERC20.sol#L84
https://github.com/code-423n4/2023-09-centrifuge/blob/main/src/PoolManager.sol#L223

Vulnerability details

Impact

_DOMAIN_SEPARATOR is not updated, when name of token is changed

Proof of Concept

This is similar to the one that i have already submited. However, i believe that this is separate issue, because in case if first one is fixed, this one still remains. While first bug is about wrong initialization, this one is about updating metadata of contract which is a part of functionality of protocol.
Here is similar issue on c4.

According to the EIP-712 in case if name, version or any other fields in the _DOMAIN_SEPARATOR is changed, then all previous signatures should not be valid anymore.

Tranche token metadata can be changed if needed. This is handled by PoolManager.updateTrancheTokenMetadata function. This function will change name field, which is part of _DOMAIN_SEPARATOR.
The problem is that after changing the name field, _DOMAIN_SEPARATOR will not be recalculated, which means that all signatures that were signed before will be still valid. Also as i have described in another report, user's will see that Tranche token name is not same as in the domain separator that they should sign, so users will likely reject signing. And people who will craft messages themselves will use real updated name to create domain separator, so it will not match and permit will revert.

Tools Used

VsCode

Recommended Mitigation Steps

When you update name, then recalculate domain separator.

Assessed type

Error

[c4-pre-sort]

raymondfam marked the issue as sufficient quality report

[c4-pre-sort]

raymondfam marked the issue as duplicate of #146

[c4-judge]

gzeon-c4 marked the issue as satisfactory