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Report #33038
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Report #33038

Report Date
July 9, 2024
Status
Closed
Payout

Unauthorized Function Addition Vulnerability in LibDiamond

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Report Info

Report ID

#33038

Report type

Smart Contract

Has PoC?

Yes

Target

https://etherscan.io/address/0xC1E088fC1323b20BCBee9bd1B9fC9546db5624C5

Impacts

Direct theft of any user funds, whether at-rest or in-motion, other than unclaimed yield

Description

The LibDiamond library, which facilitates adding, replacing, and removing functions from a smart contract using the diamond standard, has a critical flaw. It lacks proper access control in the function responsible for adding new functionalities. This oversight allows an attacker to introduce unauthorized functions into the diamond contract, potentially compromising the entire system.

Vulnerability Details

Function: addFunctions Location: Line 94 in the provided contract code Description: This function adds new functions to the diamond by updating internal mappings. Access Control Issue:

Missing Control: There are no checks to ensure that only authorized entities can call addFunctions. Risk: This allows anyone to call this function and add their own functions, including potentially malicious ones. Potential Exploit Scenario:

Attack Method: An attacker could call the addFunctions function and introduce functions that perform malicious actions. Impact: This could lead to unauthorized control of the contract, enabling the attacker to steal funds or disrupt operations.

Impact Details

Financial Losses: The attacker could add functions that transfer funds to their own address, resulting in direct financial theft. Operational Disruption: Malicious functions could disrupt the normal operations of the contract, causing it to malfunction or behave unpredictably. Reputational Damage: Users would lose trust in the platform due to security vulnerabilities, potentially leading to a loss of users and business opportunities.

References

EIP-2535 Diamond Standard https://www.quicknode.com/guides/ethereum-development/smart-contracts/the-diamond-standard-eip-2535-explained-part-1 Solidity Documentation https://docs.soliditylang.org/en/v0.8.26/

Proof of concept

pragma solidity ^0.7.6;

import "./LibDiamond.sol";

contract MaliciousContract { function exploit() external { bytes4[] memory selectors = new bytes4; selectors[0] = this.maliciousFunction.selector; LibDiamond.addFunctions(address(this), selectors); }

function maliciousFunction() external {
    // Code to perform malicious actions, such as transferring funds
}

} Add access control checks to the addFunctions, replaceFunctions, and removeFunctions functions. Ensure that only the contract owner or an authorized administrator can call these functions. Perform a comprehensive security audit on the LibDiamond library to find and fix any other potential vulnerabilitiesInform your users about the security measures being taken and the importance of only allowing trusted code to interact with your contracts

Immunefi Response

We have reviewed your submission, but unfortunately, we are closing the report for the following reasons:
  • The submission contains the output of an automated scanner without demonstrating that it is a valid issue.
  • The submission lacks the required information regarding the vulnerability's impact on the reported asset.

As per the bug bounty program's policy, we require all submissions to be accompanied by a working Proof of Concept (PoC) that demonstrates the vulnerability's existence and impact. Since the submission doesn't provide any proof of the vulnerability's existence, we have decided to close it.

Please note that the project will receive a report of the closed submission and may choose to re-open it, but they are not obligated to do so.