First Flight #15: Mondrian Wallet

Summary

The _validateSignature function in the MondrianWallet contract is responsible for validating the signature of user operations. However, the function lacks a mechanism to handle cases where the signature validation fails. This oversight could lead to incorrect validation results, potentially allowing unauthorized operations.

Vulnerability Details

The _validateSignature function does not account for the scenario where the signature recovery fails, which is indicated by a zero address being returned. Specifically, the function should check if the recovered address is the zero address and return SIG_VALIDATION_FAILED if it is.

The code above always returns SIG_VALIDATION_SUCCESS, regardless of whether the signature is valid or not. This can lead to unauthorized operations being incorrectly validated as legitimate.

Impact

The absence of a signature failure check can have significant security implications:

Unauthorized Transactions: Malicious actors could exploit this vulnerability to execute unauthorized transactions.

Security Breach: The integrity of the MondrianWallet contract can be compromised, leading to potential financial losses and a breach of trust.

Operational Risk: Failure to detect invalid signatures could lead to operational risks, including the execution of invalid user operations.

Tools Used

Manual review

Recommendations

Update the _validateSignature function to include a check for signature validation failure.