First Flight #19: Mondrian Wallet v2

Summary

This report outlines critical security risks and functional concerns in the Mondrian Wallet v2 implemented on zkSync. Key areas include upgradeable contract mechanisms, access control, signature validation, and potential mismanagement of nonces.

Vulnerability Details

1. Upgrade Security:

   • The _authorizeUpgrade function lacks explicit restrictions, potentially allowing unauthorized upgrades if the access control is compromised.

2. Role-Based Access Mismanagement:

   • Custom access controls are used without comprehensive management and auditing mechanisms, increasing the risk of role abuse or misconfiguration.

3. Signature Validation Weakness:

   • Uses ECDSA.recover for transaction validation without sufficient safeguards against signature malleability or other exploits.

4. Nonce Handling Issues:

   • Nonce management may not robustly prevent replay attacks, especially in scenarios involving asynchronous transactions or network delays.

Impact

• These vulnerabilities could lead to unauthorized access, funds loss, replay attacks, or unexpected behaviors in contract execution. They undermine the wallet's integrity and user trust.

Tools Used

• Manual code review

• LLM

Recommendations

• Implement strict checks in _authorizeUpgrade to ensure only authorized entities can initiate upgrades.

• Enhance role management and audit mechanisms for all sensitive operations.

• Introduce additional checks and balances in signature validation processes.

• Improve nonce management to ensure transaction order integrity and prevent replay attacks.