Liquid Staking

Github
https://github.com/Cyfrin/2024-09-stakelink/blob/main/contracts/linkStaking/FundFlowController.sol

Summary

This report outlines a potential vulnerability in the smart contract concerning the claim periods associated with unbonding. The vulnerability arises from the manipulation of block timestamps, which could lead to unauthorized claims and affect the fairness of the reward distribution system.

Vulnerability Details

The vulnerability is linked to the following lines of code:

Key Issues:

1. Block Timestamp Manipulation: Miners can influence block.timestamp, allowing them to claim rewards outside the intended time frame.

2. Reentrancy Risk: If the claim function interacts with external contracts, it could be vulnerable to reentrancy attacks.

3. Variable Manipulation: Changing unbondingPeriod or claimPeriod could create unfair advantages for certain users.

Impact

The identified vulnerabilities could lead to:

• Unauthorized Claims: Attackers may exploit the claim mechanism to receive rewards prematurely or deny legitimate claims.

• Financial Losses: Users may face financial harm due to the exploitation of the contract, eroding trust in the system.

• System Integrity Risks: Compromised fairness in reward distribution could diminish user confidence in the contract.

Tools Used

Manual Code Review

Recommendations

• Use block numbers in conjunction with timestamps to reduce reliance on block.timestamp.

• Apply the Checks-Effects-Interactions pattern to prevent reentrancy vulnerabilities.

• Limit changes to unbondingPeriod and claimPeriod through governance mechanisms or make them immutable.

• Add events to log claims and state changes for better transparency and accountability.