Submitted by jayjonah8, also found by cmichel and IllIllI
https://github.com/skalenetwork/ima-c4-audit/blob/main/contracts/schain/TokenManagers/TokenManagerERC20.sol#L298
https://github.com/skalenetwork/ima-c4-audit/blob/main/contracts/schain/TokenManagers/TokenManagerERC20.sol#L303
In TokenManagerERC20.sol the _exit() function makes use of transferFrom() instead of using safeTransferFrom().   Tokens that dont correctly implement the latest EIP20 spec will be unusable in the protocol as they revert the transaction because of the missing return value.
https://github.com/skalenetwork/ima-c4-audit/blob/main/contracts/schain/TokenManagers/TokenManagerERC20.sol#L298
https://github.com/skalenetwork/ima-c4-audit/blob/main/contracts/schain/TokenManagers/TokenManagerERC20.sol#L303
Its recommended to use OpenZeppelins SafeERC20 versions with the safeTransfer and safeTransferFrom functions that handle the return value check as well as non-standard-compliant tokens.
cstrangedk (SKALE) disputed, disagreed with severity and commented:
GalloDaSballo (judge) decreased severity to Medium and commented:
