Submitted by CertoraInc
AxelarGateway.sol#L545-L548
AxelarGatewayProxy.sol#L16-L24
As written in the solidity documentation, the low-level functions call, delegatecall and staticcall return true as their first return value if the account called is non-existent, as part of the design of the EVM. Account existence must be checked prior to calling if needed.
The low-level functions call and delegatecall are used in some places in the code and it can be problematic. For example, in the _callERC20Token of the AxelarGateway contract there is a low level call in order to call the ERC20 functions, but if the given tokenAddress doesnt exist success will be equal to true and the function will return true and the code execution will be continued like the call was successful.
Another place that this can happen is in AxelarGatewayProxys constructor
If the gatewayImplementation address doesnt exist, the delegate call will return true and the function wont revert.
Remix, VS Code
Check before any low-level call that the address actually exists, for example before the low level call in the callERC20 function you can check that the address is a contract by checking its code size.
deluca-mike (Axelar) confirmed, but disagreed with severity and commented:
0xean (judge) commented:
