Audit name:
[SCA] Moow | BEP20 | Aug2023
Date:
Aug 9, 2023
Table of Content
Introduction
We express our gratitude to the Moow team for the collaborative engagement that enabled the execution of this Smart Contract Security Assessment.
MOOW is merging Art, Crypto, Sport and Games together. The main feature of MOOW is the use of the user's heart rate to implement the Move-To-Earn mechanic instead of GPS. This feature allows users to engage in ANY sport or non-sport activity that brings the heart rate out of rest.
| title | content |
|---|---|
| Platform | BNB Chain |
| Language | Solidity |
| Tags | BEP20 |
| Timeline | 12/07/2023 - 08/08/2023 |
| Methodology | https://hackenio.cc/sc_methodology→ |
Review Scope | |
|---|---|
| Repository | https://github.com/superchainers/mw_chain/tree/main/contracts→ |
| Commit | 6e2ff3d4c389937208e4d415879df60a914e93ac |
Review Scope
- Commit
- 6e2ff3d4c389937208e4d415879df60a914e93ac
Audit Summary
10/10
69.05%
8/10
8/10
The system users should acknowledge all the risks summed up in the risks section of the report
Document Information
This report may contain confidential information about IT systems and the intellectual property of the Customer, as well as information about potential vulnerabilities and methods of their exploitation.
The report can be disclosed publicly after prior consent by another Party. Any subsequent publication of this report shall be without mandatory consent.
Document | |
|---|---|
| Name | Smart Contract Code Review and Security Analysis Report for Moow |
| Audited By | Hacken |
| Website | https://www.moow.run/→ |
| Changelog | 19/07/2023 – Initial Review |
| 08/08/2023 – Second Review |
Document
- Name
- Smart Contract Code Review and Security Analysis Report for Moow
- Audited By
- Hacken
- Website
- https://www.moow.run/→
- Changelog
- 19/07/2023 – Initial Review
- 08/08/2023 – Second Review
System Overview
Moow Deal is a BEP20 upgradable token implementation with the following contracts:
BEP20TokenImplementation — upgradable BEP-20 token implementation with several customizations. Users are allowed to execute one transfer per each block. It has the following attributes: \-Name: will be specified during the deployment. \-Symbol: will be specified during the deployment. \-Decimals: will be specified during the deployment. \-Total supply: Unlimited.
BEP20UpgradeableProxy — a contract that allows owner to manage proxy and logic contracts.
IBEP20 — interface of the BEP20TokenImplementation contract.
Privileged roles
The owner of the BEP20TokenImplementation contract can:
renounce the ownership to address zero.
transfer ownership.
mint tokens.
The administrator role of BEP20UpgradeableProxy contract can:
update the logic contract.
Executive Summary
Documentation quality
The total Documentation quality score is 8 out of 10.
Functional requirements are provided, but there is a contradiction in the docs. It is stated that “This document provides the technical details about TIC and TAC tokens“ in readme file, but in the repo, only TIC token is present.
Technical description is provided.
NatSpec is followed.
Code quality
The total Code quality score is 8 out of 10.
The code includes some redundant declarations.
Style guide and best practices’ violation is detected.
The development environment is configured.
Test coverage
Code coverage of the project is 69.05% (branch coverage), with a mutation score of 77%.
Test coverage is not applicable in security score for projects less than 250 lines of code.
Deployment and basic user interactions are covered with tests.
Some functionalities and multi-user interactions are not covered for BEP20TokenImplementation contract.
Security score
Upon auditing, the code was found to contain 2 critical, 0 high, 0 medium, and 1 low severity issues. Out of these, 2 issues have been addressed and resolved, leading to a security score of 10 out of 10.
All identified issues are detailed in the “Findings” section of this report.
Summary
The comprehensive audit of the customer's smart contract yields an overall score of 9.4. This score reflects the combined evaluation of documentation, code quality, test coverage, and security aspects of the project.
Risks
The owner of BEP20TokenImplementation contract can mint unlimited amount of tokens.
BEP20TokenImplementation contract is upgradeable, meaning that decimals, mintable status, total number of minted tokens and start block can be changed any time. Moreover, even though the owner’s abilities are restricted by making the owner address zero, a new owner address can be assigned.
Findings
Code ― | Title | Status | Severity | |
|---|---|---|---|---|
| F-2023-1094 | Funds Lock | fixed | Critical | |
| F-2023-1093 | Data Inconsistency | fixed | Critical | |
| F-2023-109 | Floating Pragma | unfixed | Low | |
| I-2023-030 | Redundant Import | unfixed | Observation | |
| I-2023-0304 | CEI Pattern Violation | unfixed | Observation | |
| I-2023-030 | Functions That Can Be Declared External | fixed | Observation | |
| I-2023-0302 | Redundant Function | fixed | Observation | |
| I-2023-030 | Style Guide Violation | unfixed | Observation | |
| I-2023-0300 | Redundant Use of SafeMath | fixed | Observation |
Appendix 1. Severity Definitions
When auditing smart contracts, Hacken is using a risk-based approach that considers Likelihood, Impact, Exploitability and Complexity metrics to evaluate findings and score severities.
Reference on how risk scoring is done is available through the repository in our Github organization:
Severity | Description |
|---|---|
Critical | Critical vulnerabilities are usually straightforward to exploit and can lead to the loss of user funds or contract state manipulation. |
High | High vulnerabilities are usually harder to exploit, requiring specific conditions, or have a more limited scope, but can still lead to the loss of user funds or contract state manipulation. |
Medium | Medium vulnerabilities are usually limited to state manipulations and, in most cases, cannot lead to asset loss. Contradictions and requirements violations. Major deviations from best practices are also in this category. |
Low | Major deviations from best practices or major Gas inefficiency. These issues will not have a significant impact on code execution, do not affect security score but can affect code quality score. |
Severity
- Critical
Description
- Critical vulnerabilities are usually straightforward to exploit and can lead to the loss of user funds or contract state manipulation.
Severity
- High
Description
- High vulnerabilities are usually harder to exploit, requiring specific conditions, or have a more limited scope, but can still lead to the loss of user funds or contract state manipulation.
Severity
- Medium
Description
- Medium vulnerabilities are usually limited to state manipulations and, in most cases, cannot lead to asset loss. Contradictions and requirements violations. Major deviations from best practices are also in this category.
Severity
- Low
Description
- Major deviations from best practices or major Gas inefficiency. These issues will not have a significant impact on code execution, do not affect security score but can affect code quality score.
Appendix 2. Scope
The scope of the project includes the following smart contracts from the provided repository:
Scope Details | |
|---|---|
| Repository | https://github.com/superchainers/mw_chain/tree/main/contracts→ |
| Commit | 6e2ff3d4c389937208e4d415879df60a914e93ac |
| Whitepaper | Provided→ |
| Requirements | Provided |
| Technical Requirements | Provided |
Scope Details
- Commit
- 6e2ff3d4c389937208e4d415879df60a914e93ac
- Whitepaper
- Provided→
- Requirements
- Provided
- Technical Requirements
- Provided