1. Executive Summary
Overall Risk Assessment: Low Risk
The Hydro2coin (HY2CO) smart contract has undergone a comprehensive static code analysis. The contract demonstrates solid security practices through its use of industry-standard OpenZeppelin libraries and follows established patterns for ERC20 token implementation. No critical or high-severity vulnerabilities were identified during the static analysis phase.
Critical Issues
High Issues
Medium Issues
Low Issues
Informational
- Utilizes reputable OpenZeppelin contracts (ERC20, Burnable, Ownable2Step)
- Implements SafeERC20 for secure token transfers
- Protected against reentrancy attacks through proper design
- No integer overflow/underflow vulnerabilities (Solidity 0.8.x SafeMath)
- Clear access control mechanisms with two-step ownership transfer
- Conduct external security audit by professional firm before mainnet deployment
- Implement time-locks for critical owner functions
- Consider multi-signature wallet for owner operations
- Monitor on-chain activity post-deployment for unusual patterns
2. Contract Information
2.1 Basic Details
| Property | Value |
|---|---|
| Contract Name | Hydro2coin |
| Token Symbol | HY2CO |
| Token Decimals | 18 |
| Total Supply | 105,000,000,000 HY2CO (105 Billion) |
| Contract Address | 0x18733dBBD459070d7A1861899061830a45BEb0e3 |
| Compiler Version | Solidity ^0.8.0 |
| License | MIT |
2.2 Initial Distribution
Upon deployment, the entire token supply of 105,000,000,000 HY2CO tokens was minted to the address:
2.3 Contract Features
- ERC20 Standard: Full compliance with ERC20 token standard
- Burnable: Token holders can burn their tokens
- Owner-Controlled Recovery: Owner can recover accidentally sent tokens
- Uniswap Integration: Built-in support for Uniswap V2 liquidity pools
- Two-Step Ownership: Enhanced security for ownership transfers
3. Technical Overview
3.1 Contract Architecture
The Hydro2coin contract employs a modular architecture built upon OpenZeppelin's battle-tested smart contract libraries. This approach ensures code reliability and reduces the attack surface by leveraging extensively audited implementations.
3.2 Inheritance Structure
3.3 Libraries Used
OpenZeppelin Contracts (v4.x+)
- ERC20: Standard implementation of the ERC20 token interface with minting, burning, and transfer functionality
- ERC20Burnable: Extension allowing token holders to destroy their own tokens, reducing total supply
- Ownable2Step: Enhanced ownership management requiring two-step process for ownership transfer, preventing accidental transfers
- SafeERC20Remastered: Custom wrapper ensuring safe ERC20 token operations with proper error handling
Uniswap V2 Integration
- IUniswapV2Router02: Interface for interacting with Uniswap V2 Router for liquidity and swaps
- IUniswapV2Factory: Interface for creating and managing Uniswap V2 trading pairs
3.4 Key Contract Variables
| Variable | Type | Purpose |
|---|---|---|
| uniswapV2Pair | address | Stores the Uniswap V2 pair address for HY2CO/WETH trading |
| uniswapV2Router | IUniswapV2Router02 | Reference to Uniswap V2 Router for DEX operations |
3.5 Constructor Logic
The constructor performs the following operations:
- Initializes the ERC20 token with name "Hydro2coin" and symbol "HY2CO"
- Mints the total supply of 105,000,000,000 tokens (with 18 decimals)
- Transfers all minted tokens to the specified initial holder address
- Sets the contract deployer as the initial owner
afterConstructor function, which must be called by the owner to set up the trading pair and router.
4. Security Analysis
4.1 Reentrancy Protection
The contract follows the Checks-Effects-Interactions pattern and does not contain complex state modifications followed by external calls. OpenZeppelin's ERC20 implementation inherently protects against reentrancy in transfer operations.
Analysis:
- No external calls precede state changes in custom functions
- Token recovery functions use SafeERC20 which prevents reentrancy
- Standard ERC20 transfer operations follow secure patterns
- No delegate calls or complex interactions with untrusted contracts
4.2 Integer Overflow/Underflow Protection
The contract uses Solidity 0.8.x which has built-in overflow/underflow protection. All arithmetic operations automatically revert on overflow or underflow.
Key Points:
- Solidity 0.8.0+ includes automatic SafeMath functionality
- No use of
uncheckedblocks that could bypass safety checks - Token supply is fixed at deployment with no minting mechanism
- All arithmetic in ERC20 operations is protected by default
4.3 Access Control Mechanisms
The contract implements robust access control through OpenZeppelin's Ownable2Step pattern, providing enhanced security for privileged operations.
Access Control Features:
- Owner-Only Functions: Protected by
onlyOwnermodifier from OpenZeppelin - Two-Step Ownership Transfer: Prevents accidental ownership loss
- Step 1: Current owner proposes new owner via
transferOwnership() - Step 2: Proposed owner must accept via
acceptOwnership()
- Step 1: Current owner proposes new owner via
- Ownership Renunciation: Owner can renounce ownership, making contract fully decentralized
4.4 External Call Safety
All external calls in the contract are properly handled with appropriate safety measures.
External Call Analysis:
- SafeERC20 Usage: The contract uses SafeERC20Remastered for all token transfers, ensuring:
- Proper handling of non-standard ERC20 implementations
- Revert on failed transfers
- Protection against tokens that don't return boolean values
- Uniswap Integration: Interactions with Uniswap contracts follow standard patterns
- Read-only calls to factory and router
- No value transfers in Uniswap setup
- One-time configuration via
afterConstructor
4.5 Token Recovery Functions
The contract implements two recovery functions to handle accidentally sent tokens:
4.5.1 recoverToken()
Purpose: Recovers HY2CO tokens accidentally sent to the contract itself.
Security:
- Owner-only access via
onlyOwnermodifier - Uses internal
_transferfunction from OpenZeppelin ERC20 - No external calls to untrusted contracts
- Cannot steal user tokens (only recovers tokens sent to contract address)
4.5.2 recoverForeignERC20()
Purpose: Recovers any ERC20 tokens (not HY2CO) accidentally sent to the contract.
Security:
- Owner-only access via
onlyOwnermodifier - Uses SafeERC20 for secure transfers
- Can only recover tokens held by the contract address
- Cannot access user balances
5. Owner Privileges Analysis
The contract grants specific privileges to the owner address. This section analyzes each privileged function and its security implications.
5.1 Owner Functions Summary
| Function | Purpose | Risk Level |
|---|---|---|
| afterConstructor() | One-time Uniswap setup | Low |
| recoverToken() | Recover HY2CO tokens | Low |
| recoverForeignERC20() | Recover foreign ERC20 tokens | Low |
| transferOwnership() | Propose new owner | Low |
| renounceOwnership() | Remove owner permanently | Info |
5.2 Detailed Analysis
afterConstructor() - Uniswap Setup
Functionality:
- Creates a Uniswap V2 trading pair for HY2CO/WETH
- Sets the Uniswap router address
- Emits event for transparency
- Can only be called once (attempting to recreate existing pair will revert)
Security Considerations:
- ✅ Owner-only access prevents unauthorized DEX configuration
- ✅ Event emission provides transparency
- ✅ Uses official Uniswap interfaces
- ⚠️ Owner must use legitimate Uniswap router address
- ⚠️ No validation of router address (relies on owner diligence)
Risk Assessment: Low
While the owner can set the router address, this is a one-time operation necessary for DEX integration. Misuse would be immediately visible on-chain.
recoverToken() - Native Token Recovery
Purpose: Allows owner to recover HY2CO tokens accidentally sent to the contract address.
Security Considerations:
- ✅ Cannot access user token balances
- ✅ Only recovers tokens held by contract itself
- ✅ Uses secure internal transfer function
- ✅ No external calls to untrusted contracts
- ℹ️ Standard feature to prevent permanent token loss
Risk Assessment: Low
This is a standard safety feature. The owner cannot steal user tokens, only recover tokens mistakenly sent to the contract.
recoverForeignERC20() - Foreign Token Recovery
Purpose: Allows owner to recover any ERC20 tokens (other than HY2CO) accidentally sent to the contract.
Security Considerations:
- ✅ Uses SafeERC20 for secure transfers
- ✅ Cannot access user balances
- ✅ Only recovers tokens held by contract address
- ⚠️ Owner can specify any token address and recipient
- ℹ️ Standard feature for multi-token recovery
Risk Assessment: Low
Legitimate recovery mechanism with no access to user funds. However, users should avoid sending tokens to the contract address.
Ownable2Step - Ownership Transfer
Enhanced Security Model:
- Step 1: Current owner calls
transferOwnership(newOwner) - Step 2: New owner must call
acceptOwnership()to complete transfer
Benefits:
- ✅ Prevents accidental ownership transfer to wrong address
- ✅ Prevents ownership transfer to address without private key access
- ✅ Requires explicit acceptance from new owner
- ✅ Pending transfer can be canceled by current owner
Risk Assessment: Low
This is a security enhancement over standard Ownable pattern, reducing risk of ownership loss.
5.3 Owner Privilege Recommendations
- Multi-Signature Wallet: Use a multi-sig wallet (e.g., Gnosis Safe) as the owner to require multiple approvals for privileged operations
- Time-Locks: Implement time-locks for critical functions to give community time to react
- Ownership Renunciation: Consider renouncing ownership after initial setup to make the contract fully decentralized
- Transparency: Publicly document the owner address and announce any ownership changes
- Router Verification: Verify Uniswap router address before calling afterConstructor()
6. Code Quality Assessment
6.1 Use of Reputable Libraries
The contract exclusively uses OpenZeppelin contracts, which are industry-standard, extensively audited, and maintained by security experts.
Library Assessment:
- OpenZeppelin v4.x+:
- Battle-tested by thousands of projects
- Regular security audits
- Active maintenance and bug fixes
- Clear documentation