Tadle

Summary

Vulnerability Details

A potential re-entrancy vulnerability exists in the withdraw function of the TokenManager.sol contract. This vulnerability can be exploited by malicious actors to withdraw more funds than they are entitled to, leading to significant financial loss.

The vulnerability is located in the following block of code within the withdraw function:

The issue arises because the contract transfers Ether to the caller (msg.sender) before updating the state to reflect the withdrawal. An attacker could exploit this by re-entering the withdraw function before the state is updated, allowing them to withdraw more funds than they are entitled to.

Scenario:

1. Initial State:

   • userTokenBalanceMap[attacker][wrappedNativeToken][balanceType] = 10 ETH

2. Attack Execution:

   • The attacker calls the withdraw function to withdraw 10 ETH.

   • The contract transfers 10 ETH to the attacker.

   • Before the state is updated, the attacker re-enters the withdraw function.

   • The contract transfers another 10 ETH to the attacker.

   • This process can be repeated multiple times, draining the contract's funds.

Impact

attackers can withdraw more funds than they are entitled to

Tools Used

Recommendations

To mitigate this vulnerability, follow the Checks-Effects-Interactions pattern. Update the state before transferring funds to prevent re-entrancy attacks