Raspy Fleece Mantaray Vulnerability Incorrect Price Validation In Oracle Contract

Jul 28, 2025 by ADMIN 82 views

Raspy Fleece Mantaray - Incorrect Validation of `report.priceD18` on `Oracle::_validatePrice`

Hey guys! Today, we're diving deep into a security vulnerability found in the Mellow Flexible Vaults project, specifically concerning the Oracle.sol contract. This issue, nicknamed "Raspy Fleece Mantaray," involves an incorrect validation of price reports, which could potentially lead to some serious problems. Let's break it down step by step.

Summary

In the Oracle.sol contract, the _validatePrice function has a flaw in how it validates initial price reports. Specifically, when prevPriceD18 is zero, the function always returns isValid = true, no matter what the new price value is. This means that a price of zero, or any other potentially invalid price, could be accepted, bypassing the intended price validation checks. This can cause unexpected behavior in the system. This vulnerability is a big deal because it compromises the integrity of the price feeds, which are crucial for the correct functioning of the vaults.

Vulnerability Details

Let's dig into the code. The issue lies within the Oracle::_validatePrice function. Here's the problematic snippet:

function _validatePrice(uint256 priceD18, DetailedReport storage report, SecurityParams memory params)
    private
    view
    returns (bool isValid, bool isSuspicious)
{
    uint256 prevPriceD18 = report.priceD18;
    if (prevPriceD18 == 0) {
        return (true, true); // Always returns isValid=true for 0 prevPriceD18
    }
    // ... rest of validation logic
}

See that if (prevPriceD18 == 0) block? When the previous price (prevPriceD18) is zero, the function immediately returns (true, true). This means isValid is always true, regardless of the priceD18 value. Think about this: it's like saying any initial price, even zero, is perfectly acceptable. This is definitely not what we want.

This function is called from _handleReport:

function _handleReport(SecurityParams memory params, uint224 priceD18, DetailedReport storage report)
    internal
    returns (bool)
{
    // ... other code
    (bool isValid, bool isSuspicious) = _validatePrice(priceD18, report, params);
    if (!isValid) {
        revert InvalidPrice(priceD18);
    }
    // ... rest of the function
}

Because _validatePrice returns isValid = true for initial reports, the InvalidPrice revert will never be triggered, even if priceD18 is zero. This is a critical flaw as it completely bypasses the price validation for the first report. The consequences of this are significant.

Impact

So, what's the big deal if a zero price is accepted? Well, a price of zero can wreak havoc in several ways. First, it can lead to incorrect valuations of assets within the vaults. Imagine calculating the value of your holdings with a zero price – it's going to be way off! Second, it can cause division-by-zero errors in other calculations that rely on this price. Any arithmetic operation involving division by zero will cause the entire transaction to fail. This could potentially halt the operation of the vaults and cause significant disruptions. Finally, and perhaps most concerning, accepting a zero price opens the door to other unexpected and undesirable behaviors within the system. The impact of this vulnerability is severe.

Recommendation

To fix this issue, we need to modify the _validatePrice function to properly validate initial price reports. The solution is to return (false, true) when prevPriceD18 is zero, effectively rejecting any initial price report that is invalid. Here's the recommended change:

function _validatePrice(uint256 priceD18, DetailedReport storage report, SecurityParams memory params)
    private
    view
    returns (bool isValid, bool isSuspicious)
{
    uint256 prevPriceD18 = report.priceD18;
    
    if (prevPriceD18 == 0) {
        return (false, true); // Reject initial price reports with isValid=false
    }
    
    // ... rest of validation logic
}

By returning false for isValid when prevPriceD18 is zero, we ensure that the InvalidPrice revert is triggered, preventing the acceptance of invalid initial prices. This is a crucial fix that will safeguard the integrity of the Mellow Flexible Vaults. The security of the system needs to ensure that this kind of situation will never happen again.

Alright, let's get a little deeper into this "Raspy Fleece Mantaray" vulnerability, guys. The name might sound a bit quirky, but the issue is quite serious, especially when we're talking about decentralized finance (DeFi) and the security of our funds. We've already covered the technical details, but let's zoom out and understand the bigger picture – why this happened, what the consequences could have been, and how we can prevent similar issues in the future.

Why Did This Happen?

Vulnerabilities like this often arise from a combination of factors. First, there might have been an oversight in the initial design or specification of the _validatePrice function. Perhaps the developers focused more on the subsequent price validations and didn't fully consider the implications of the initial price report. Second, insufficient testing could have played a role. If the test suite didn't include test cases specifically targeting the scenario where prevPriceD18 is zero, this issue might have slipped through the cracks. Third, it's possible that the code review process didn't catch this subtle flaw. Code reviews are a critical line of defense against vulnerabilities, but even experienced auditors can sometimes miss things, especially in complex codebases. Understanding the root causes of vulnerabilities is crucial for learning and improving our security practices.

Potential Consequences

Let's paint a picture of what could have happened if this vulnerability had been exploited. Imagine an attacker noticing that they can submit a zero price as the initial report. They could then manipulate the system into thinking that the value of an asset is zero. This could have several devastating consequences:

Liquidation Issues: If the vaults rely on the price feed to determine liquidation thresholds, a zero price could trigger unwarranted liquidations, causing significant losses for users.
Exploitation of Other Protocols: The vaults might interact with other DeFi protocols that also rely on accurate price data. A manipulated price feed could be used to exploit these protocols, potentially leading to further losses.
Reputational Damage: A successful attack exploiting this vulnerability would severely damage the reputation of the Mellow Flexible Vaults project, eroding user trust and confidence.

These are just a few examples of the potential damage that this vulnerability could have caused. It's a stark reminder of the importance of security in DeFi.

Preventing Future Issues

So, how can we prevent similar vulnerabilities from creeping into our code in the future? Here are some key strategies:

Robust Design and Specification: Before writing any code, it's essential to have a clear and comprehensive design specification. This specification should explicitly address edge cases and potential vulnerabilities, such as the initial price report scenario in this case.
Comprehensive Testing: A thorough test suite is crucial for catching bugs and vulnerabilities. Test cases should cover all possible scenarios, including edge cases and boundary conditions. Fuzzing and other forms of automated testing can also be valuable.
Rigorous Code Reviews: Code reviews should be conducted by experienced auditors who are familiar with common security vulnerabilities. The review process should be systematic and thorough, with reviewers paying close attention to potential edge cases and vulnerabilities.
Formal Verification: For critical components of the system, formal verification techniques can be used to mathematically prove the correctness of the code. This can provide a high level of assurance that the code behaves as expected.
Security Audits: Engaging professional security auditors to review the codebase can help identify vulnerabilities that might have been missed by the internal team.

By implementing these strategies, we can significantly reduce the risk of security vulnerabilities in our DeFi projects.

Conclusion

The "Raspy Fleece Mantaray" vulnerability highlights the importance of careful design, thorough testing, and rigorous code review in DeFi projects. While this particular issue was caught and addressed before it could be exploited, it serves as a valuable lesson for the entire community. We need to remain vigilant and continue to improve our security practices to protect users and the integrity of the DeFi ecosystem. This error teaches us how a single oversight can have a big impact in a smart contract and shows why we need to be careful and pay attention to every detail.

By fixing the _validatePrice function, the Mellow Flexible Vaults project has taken a crucial step in ensuring the security and reliability of its platform. And by learning from this experience, we can all contribute to a more secure and robust DeFi ecosystem. The most important thing is that projects and developers are continuously improving their code review and testing processes.