File location:

https://github.com/Cyfrin/2024-07-biconomy/blob/9590f25cd63f7ad2c54feb618036984774f3879d/contracts/lib/ExecLib.sol#L32-L36

Summary

The 'decodeSingle' function in the 'ExecLib' contract allows setting state variable values ​​without a maximum limit, which can lead to exploits by providing very large values. This can impact the security and integrity of the contract.

Vulnerability Details

In the 'ExecLib' contract, the 'decodeSingle' function does not limit the maximum value that can be assigned to the 'value' variable. When very large values ​​are assigned, this can cause integrity issues with the contract, including potential overflow attacks or unintended resource utilization.

Impact

• Overflow attack.

• Excessive gas consumption.

• Potential damage to contract logic.

Tools Used

• Inspection manual

• Solidity

Recommendations

Code snippet:

L32-L36

Fixed code:

To fix the problem, you can add logic to ensure that the 'value' value is within reasonable limits. For example, you can set a maximum limit for 'value'.