Smart Contract Security Auditor
Automated static analysis engine and code vulnerability scanner supporting both EVM (Solidity) and Solana (Rust / Anchor). Audit smart contracts for reentrancy, missing signer validation, account owner confusion, arbitrary CPI, and arithmetic underflow with remediation diffs.
The Billion-Dollar Imperative of Smart Contract Security
Smart contracts manage billions of dollars in self-custodial assets across decentralized exchanges, lending pools, algorithmic stablecoins, and liquidity vaults. Unlike traditional software applications where critical bugs can be remediated via backend hotfixes and database rollbacks, smart contract code is immutable by default on decentralized blockchains. Once deployed, any vulnerability in execution logic or authorization checks can be exploited permissionlessly by MEV bots and black-hat hackers within seconds.
According to industry data, over $6.5 billion has been lost to smart contract vulnerabilities since the inception of Ethereum. From the historic 2016 DAO hack to modern flash loan price manipulation attacks, over 80% of exploits stemmed not from zero-day cryptographic breakthroughs, but from preventable implementation flaws: violation of Checks-Effects-Interactions, missing signer checks, unverified account ownership, and unchecked low-level calls.
EVM vs. SVM Security Architecture: Two Radically Different Paradigms
Developers transitioning between Ethereum Virtual Machine (EVM) and Solana Sealevel Virtual Machine (SVM) frequently introduce catastrophic vulnerabilities because the two runtimes operate under diametrically opposed state models:
In the EVM, smart contracts encapsulate both executable bytecode and mutable state storage within the same address. Functions interact via internal message calls. Because an external call yields execution control to the recipient contract, reentrancy vulnerabilities arise when the caller's state is updated after the call.
In Solana, executable programs are strictly stateless. All data and token balances reside in separate, decoupled data accounts owned by programs. The runtime does not pass execution control recursively. Instead, security relies entirely on validating that every account passed to the program is genuinely signed by its authority and owned by the expected program ID.
Anatomy of an EVM Reentrancy Attack & The Checks-Effects-Interactions Pattern
The classic reentrancy bug occurs when contract code sends Ether or invokes an external target before synchronizing its internal ledger:
// Insecure: Interaction occurs before Effect
1. User requests withdraw(10 ETH);
2. Contract checks balances[msg.sender] >= 10 ETH; (Check)
3. Contract executes msg.sender.call{value: 10 ETH}(""); (Interaction)
4. Attacker fallback() immediately calls withdraw(10 ETH) again before line 5 executes!
5. balances[msg.sender] -= 10 ETH; // (Effect: Too late! State already compromised)
The fix is mathematically elegant: apply the Checks-Effects-Interactions (CEI) pattern by mutating balances[msg.sender] -= amount prior to issuing the low-level call, or inherit OpenZeppelin's battle-tested ReentrancyGuard with the nonReentrant modifier.
Solana & Anchor Security Vectors: The Missing Signer & Account Confusion Nightmare
On Solana, clients supply account references as a flat list of public keys. If an instruction deserializes an account without enforcing authorization, severe exploits occur:
1. Missing Signer Check
If an Anchor context declares pub authority: AccountInfo<'info> instead of pub authority: Signer<'info>, the Solana runtime does not require a cryptographic signature. Anyone can pass the program authority's public key and trigger admin functions.
2. Account Owner Confusion
If an account's owner program is not validated, an attacker can create a counterfeit account with identical data fields and pass it to your program. In Anchor, always verify account types using Account<'info, TokenAccount> and strict constraint = recipient.owner == authority.key() macros.
Frequently Asked Questions (FAQ)
Q:How does this tool analyze smart contract code in real-time?
The engine tokenizes the source code into an abstract syntax tree (AST) representation and matches structural patterns against our curated database of Common Weakness Enumerations (CWEs), including the SWC registry for Solidity and the Sealevel Attacks registry for Solana. It evaluates control flow, variable mutability, modifier ordering, and CPI constraints.
Q:Why does Solana lack the classic EVM reentrancy vulnerability?
The Solana Sealevel runtime does not support reentrancy within the same instruction cycle because a program cannot invoke itself recursively, and account locks prevent multiple instructions in the same transaction from simultaneously obtaining write access to the same account. However, Solana has its own distinct vulnerabilities, such as account confusion, missing owner checks, and arbitrary CPI execution.
Q:What is the Anchor framework and why is it recommended for Solana development?
Anchor is a Rust framework for Solana that introduces automatic instruction discriminators, account deserialization constraints (Signer<'info>, Account<'info, TokenAccount>), and declarative macros. It eliminates boilerplate code that frequently leads to severe authorization bypass bugs in native Solana programs.
Q:How can developers prevent integer overflow in modern Solidity and Rust?
Solidity 0.8.0+ has built-in arithmetic overflow/underflow checks that revert automatically unless explicitly wrapped in an unchecked {} block. In Rust for Solana, developers must explicitly use checked arithmetic methods such as .checked_add(), .checked_sub(), or .checked_mul(), because release compilation profiles can silently overflow or panic unexpectedly.
Q:Can I export the audit findings as a formal Markdown report?
Yes. After running the audit, click the "Export Report" button on the severity breakdown card. This generates a standardized Markdown audit report containing the security rating, line numbers, vulnerability descriptions, impact statements, and copyable remediation diffs.