Summary:

The stakeFor function involves transferring tokens and updating state variables. The current implementation of the function allows for a reentrancy attack because it does not follow the Check-Effects-Interactions (CEI) pattern. Ensuring that all state updates are completed before any external calls are made is crucial to prevent such attacks.

Vulnerability Details:

found in stakeFor function in the TempleGoldStaking.sol smart contract.

Impact:

If a reentrancy attack is possible, an attacker could exploit the contract to call the function repeatedly before the initial execution completes, potentially leading to inconsistencies and unauthorized operations, resulting in loss of funds or other unexpected behaviors.

Code Analysis

The function stakeFor currently looks like this:

In this code, the safeTransferFrom call is an external interaction that occurs before state updates are fully completed, which violates the CEI pattern.

Proof of Concept (PoC) / Scenario

• An attacker could craft a malicious stakingToken contract to re-enter the stakeFor function during the safeTransferFrom call.

Tools Used:

Manual audit, Foundry

Recommendations:

To prevent reentrancy attacks, follow the CEI pattern: perform all state changes before making external calls. Reorder the function to update the state variables before the external call.

Example Mitigation: