Flow

Summary

The transferAdmin function in the Adminable contract allows transferring admin privileges to a new address but does not validate that the new admin address is not the zero address. This could lead to locking the contract out of all admin functionalities.

Finding Description

The transferAdmin function does not include a check to prevent the new admin address from being set to the zero address. The lack of this validation breaks the security guarantee that the contract will always have a valid admin. If a malicious actor (or an unintended call) sets the new admin to 0x0, it will permanently prevent any admin operations, rendering the contract non-functional for admin-restricted actions.

This vulnerability could be exploited by a malicious user if they gain access to the current admin account and call transferAdmin with the zero address. Once executed, the admin's control over the contract will be irreversibly lost.

Vulnerability Details

• Function: transferAdmin(address newAdmin)

• Location: Adminable.sol

• Description: The function is intended to allow the current admin to transfer admin rights but lacks a check for the zero address.

Impact

The impact assessment is classified as high because this vulnerability directly leads to a loss of functionality for admin-controlled functions. If the admin address is set to zero, no valid address can execute onlyAdmin functions, which could effectively lock all critical administrative capabilities of the contract.

Proof of Concept

The following example demonstrates how a malicious actor could exploit this issue:

1. The current admin (e.g., 0xABC...) calls transferAdmin(0x0).

2. After executing this call, the admin address is set to 0x0, making all admin-restricted functionalities inaccessible.

Recommendations

To fix this issue, it is recommended to add a check in the transferAdmin function to prevent the admin from being set to the zero address. Here is a code snippet with the recommended fix:

By implementing this check, the contract will ensure that admin privileges cannot be transferred to an invalid address, maintaining the contract's intended functionality and security.

File Location

Adminable.solTransfer Admin Functionality