web3-grep-arsenal

name	web3-grep-arsenal
description	Master grep command arsenal for Web3 smart contract auditing. Use when starting a new protocol scan, before deep code review, or when hunting specific vulnerability classes.
Contains	10 grep blocks for all major vuln classes, tier ranking, protocol-specific patterns, 2025 new patterns, copy-paste ready blocks.

GREP ARSENAL — MASTER REFERENCE

All grep commands in one place. Run in the first 30 minutes of any new target. Replaces: 03-grep-surface-map, 14-grep-master-patterns + grep sections from 04-13

---

HOW TO USE THE SURFACE MAP

Process:

1. Run ALL 10 blocks below (takes ~5 min)
2. Collect all results in a notes file
3. Tier-rank the hits (see Tier System below)
4. In pass 1: READ everything, DON'T investigate yet
5. In pass 2: Deep-dive on Tier 1 + 2 items

Tier System:

• Tier 1 — Near privileged code, external calls, or state changes with no guards → Investigate first
• Tier 2 — Interesting patterns that need context before judging → Investigate after Tier 1
• Tier 3 — Informational only (documentation, test files, comments) → Skip unless Tier 1+2 exhausted

---

THE 10 GREP BLOCKS (Copy-Paste Each)

Block 1 — Access Control

echo "=== ACCESS CONTROL ===" && \
grep -rn "tx\.origin" src/ --include="*.sol" && \
grep -rn "msg\.sender == owner\b" src/ --include="*.sol" && \
grep -rn "modifier only" src/ --include="*.sol" -A5 && \
grep -rn "onlyOwner\|onlyAdmin\|onlyRole" src/ --include="*.sol" | wc -l && \
grep -rn "def admin_\|router\..*admin\|function.*[Aa]dmin" src/ --include="*.sol"

Red flags:

• tx.origin used for auth → Tier 1 (phishing vector)
• Modifier uses if (condition) { _; } without else → Tier 1 (silent bypass — function still executes for unauthorized callers)
• onlyOwner count << total external function count → likely missing guards on siblings

Block 2 — Reentrancy

echo "=== REENTRANCY ===" && \
grep -rn "\.call{value\|\.call(" src/ --include="*.sol" && \
grep -rn "\.transfer(\|\.send(" src/ --include="*.sol" && \
grep -rn "safeTransfer\|safeTransferFrom" src/ --include="*.sol" && \
grep -rn "onERC721Received\|onERC1155Received\|tokensReceived" src/ --include="*.sol" && \
grep -rn "nonReentrant\|ReentrancyGuard" src/ --include="*.sol"

Red flags:

• .call{value:} or safeTransfer BEFORE state updates in same function → Tier 1 (CEI violation)
• onERC721Received/onERC1155Received hooks present → check for reentrancy path
• External calls present but nonReentrant missing → verify CEI is followed

Block 3 — Oracle / Price

echo "=== ORACLE / PRICE ===" && \
grep -rn "slot0\b" src/ --include="*.sol" && \
grep -rn "getReserves()" src/ --include="*.sol" && \
grep -rn "latestRoundData\|latestAnswer" src/ --include="*.sol" && \
grep -rn "updatedAt" src/ --include="*.sol" && \
grep -rn "block\.timestamp" src/ --include="*.sol" | grep -v "//\|test\|Test" | head -20

Red flags:

• slot0() used for price → Tier 1 (Uniswap V3 spot, flash-loan manipulable)
• getReserves() used for price → Tier 1 (Uniswap V2 spot, flash-loan manipulable)
• latestRoundData without updatedAt check → Tier 1 (stale Chainlink price)
• latestAnswer → Tier 1 (deprecated, no round validation)

Block 4 — Arithmetic / Math

echo "=== ARITHMETIC ===" && \
grep -rn "unchecked {" src/ --include="*.sol" && \
grep -rn "/ \|/=" src/ --include="*.sol" | grep -v "//\|test\|Test" | head -30 && \
grep -rn "mulDiv\|FullMath\|PRBMath" src/ --include="*.sol" && \
grep -rn "\* 10\*\*\|* 1e18\|* WAD\|* RAY" src/ --include="*.sol"

Red flags:

• unchecked {} blocks → manually verify each (Solidity 0.8+ unwraps here)
• Division before multiplication (a / b * c) → precision loss
• / 1e18 in contract that handles 6-decimal tokens → decimal mismatch

Block 5 — Input Validation

echo "=== INPUT VALIDATION ===" && \
grep -rn "address(0)\b" src/ --include="*.sol" && \
grep -rn "require.*length\|\.length ==" src/ --include="*.sol" && \
grep -rn "delegatecall" src/ --include="*.sol" && \
grep -rn "abi\.decode\|abi\.encodePacked" src/ --include="*.sol" | head -20

Red flags:

• delegatecall with user-controlled target → Tier 1 (arbitrary code execution)
• abi.decode on user-supplied calldata without length validation → Tier 1
• Array params in batch functions without dedup check → Tier 1 (double-count attack)

Block 6 — Token Handling

echo "=== TOKEN HANDLING ===" && \
grep -rn "IERC20\.\|ERC20\." src/ --include="*.sol" | grep "transfer\b\|transferFrom\b" && \
grep -rn "SafeERC20\|safeTransfer\b" src/ --include="*.sol" | head -10 && \
grep -rn "balanceOf(address(this))" src/ --include="*.sol" && \
grep -rn "permit(" src/ --include="*.sol" | grep -v "//\|IERC20Permit" && \
grep -rn "try.*permit\|catch.*permit" src/ --include="*.sol"

Red flags:

• token.transfer() without SafeERC20.safeTransfer() → Tier 1 (return value unchecked, fails silently on old USDT)
• balanceOf(address(this)) for pricing/shares → Tier 1 (donation attack vector)
• permit() without try/catch wrapper → Tier 2 (frontrun DoS possible)

Block 7 — ERC4626 / Vault

echo "=== ERC4626 / VAULT ===" && \
grep -rn "totalAssets\|convertToShares\|previewDeposit\|previewMint" src/ --include="*.sol" && \
grep -rn "_decimalsOffset\|decimalsOffset\|virtual_shares\|dead.*shares" src/ --include="*.sol" && \
grep -rn "shares.*supply\|totalSupply\|mint.*shares" src/ --include="*.sol" | head -20

Red flags:

• ERC4626 present but _decimalsOffset() NOT present → Tier 1 (first depositor inflation)
• totalAssets() uses balanceOf(address(this)) → Tier 1 (donation attack)
• mint() or deposit() called without same validation path → Tier 1 (MetaPool bug: mint skipped receipt check)

Block 8 — Proxy / Upgradeable

echo "=== PROXY / UPGRADE ===" && \
grep -rn "_authorizeUpgrade\|upgradeTo\|upgradeToAndCall" src/ --include="*.sol" && \
grep -rn "initialize(" src/ --include="*.sol" | grep -v "//\|test\|Test" && \
grep -rn "_disableInitializers\|initializer\b\|Initializable" src/ --include="*.sol" && \
grep -rn "StorageSlot\|ERC1967\|TransparentProxy\|UUPSUpgradeable" src/ --include="*.sol"

Red flags:

• _authorizeUpgrade() without onlyOwner or role check → Tier 1 (anyone can upgrade)
• initialize() without initializer modifier → Tier 1 (re-initialization possible)
• Proxy present but _disableInitializers() NOT in impl constructor → Tier 1 (impl attackable)

Block 9 — Signature / Replay

echo "=== SIGNATURES ===" && \
grep -rn "ecrecover\|ECDSA\.recover" src/ --include="*.sol" && \
grep -rn "chainId\|block\.chainid\|DOMAIN_SEPARATOR" src/ --include="*.sol" && \
grep -rn "nonces\[" src/ --include="*.sol" && \
grep -rn "keccak256.*abi\.encode" src/ --include="*.sol" | head -20

Red flags:

• ecrecover present but chainId/DOMAIN_SEPARATOR NOT present → Tier 1 (cross-chain replay)
• ecrecover without nonce → Tier 1 (same-chain replay)
• ecrecover return not checked against address(0) → Tier 1 (invalid sigs succeed)

Block 10 — State Completeness / Access

echo "=== STATE COMPLETENESS ===" && \
grep -rn "grantRole\|revokeRole\|hasRole" src/ --include="*.sol" && \
grep -rn "bytes32.*ROLE\s*=" src/ --include="*.sol" && \
grep -rn "function.*migrate\|function.*batch.*stake\|function.*multiStake" src/ --include="*.sol" -A10 && \
grep -rn "} catch" src/ --include="*.sol" -A5 | grep -A5 "revert\|Error" && \
grep -rn "cached\|_cache\|lastKnown\|storedBalance" src/ --include="*.sol"

Red flags:

• Role defined but grantRole() call for that role NOT found anywhere → Tier 1 (role permanently empty)
• Array-based function: flag = true OUTSIDE/AFTER loop → Tier 1 (empty array bypass)
• } catch { revert } on critical path → Tier 2 (liveness DoS if external changes)
• Cache variable initialized to 0 with no first-access guard → Tier 1 (uninitialized cache)

---

PROTOCOL-SPECIFIC PATTERNS

Yield Aggregator (like Ern, Yearn, Beefy)

grep -rn "cumulativeReward\|rewardPerShare\|accRewardPerShare" src/ --include="*.sol"
grep -rn "harvestCooldown\|canHarvest\|performHarvest\|_harvest" src/ --include="*.sol"
grep -rn "totalDeposited\|totalPrincipal" src/ --include="*.sol"
# Check: does cumulativeReward always update before user checkpoint?

Lending Protocol (like Aave, Compound)

grep -rn "collateral\|borrow\|liquidat" src/ --include="*.sol"
grep -rn "healthFactor\|isSolvent\|isLiquidatable" src/ --include="*.sol"
grep -rn "interest.*accrual\|accrueInterest\|indexIncrease" src/ --include="*.sol"
grep -rn "amplification\|A_PARAMETER\|getA()" src/ --include="*.sol"
# Check: is price oracle manipulation possible? Is interest accrual order correct?

AMM / DEX

grep -rn "getReserves\|reserve0\|reserve1" src/ --include="*.sol"
grep -rn "slot0\|sqrtPriceX96\|tick\b" src/ --include="*.sol"
grep -rn "K\s*=\|invariant\|_invariant" src/ --include="*.sol"
grep -rn "amountOutMin\|minAmountOut\|deadline" src/ --include="*.sol"
# Check: is spot price used for any security decision? Missing slippage?

Staking / Restaking

grep -rn "epoch\|currentEpoch\|lastEpoch\|epochId" src/ --include="*.sol"
grep -rn "unstake\|migrate\|slash\|jailValidator" src/ --include="*.sol"
grep -rn "validatorIds\|stakeIds\|delegateIds" src/ --include="*.sol"
# Check: can same ID be passed twice? Empty array skips state reset?

ZK / Proof Contracts

grep -rn "verifyProof\|IVerifier\|publicInputs\b" src/ --include="*.sol"
grep -rn "return true" src/ --include="*.sol" | grep -i "verify\|proof"
grep -rn "require.*inputs\[0\]\|rangeCheck\|MAX_BALANCE" src/ --include="*.sol"
# Check: are public inputs range-checked after proof verification?

---

2025 NEW PATTERN SCANS

# ERC4626 near-empty vault (inflation variant, now widespread)
grep -rn "totalAssets\b" src/ --include="*.sol" -A10 | grep "balanceOf\|balance()"
# If totalAssets() uses raw balanceOf → donation attack risk

# EIP-2612 permit frontrun DoS
grep -rn "permitAndDeposit\|permitAndStake\|permitAndBorrow" src/ --include="*.sol"
grep -rn "try.*permit\|catch.*permit" src/ --include="*.sol"
# Missing try/catch around permit = DoS possible

# Decimal precision mismatch (6 vs 18 decimals)
grep -rn "/ 1e18\|/ WAD" src/ --include="*.sol"
grep -rn "decimals()\|IERC20Metadata" src/ --include="*.sol"
# / 1e18 WITHOUT decimals() call in same function = decimal mismatch candidate

# Uninitialized cache
grep -rn "uint256.*cached\|uint128.*cached\|int256.*cached" src/ --include="*.sol"
# Cache initialized to 0 with no first-access sync = uninitialized cache bug

# Empty array bypass
grep -rn "= true;" src/ --include="*.sol" -B15 | grep -B15 "for.*calldata"
# flag = true AFTER a loop that can be empty = bypass critical

# Streaming/continuous precision (per-second rewards)
grep -rn "rewardPerSecond\|ratePerSecond\|flowRate\|perSecond" src/ --include="*.sol"
grep -rn "uint128.*reward\|uint96.*rate" src/ --include="*.sol"
# uint128 accumulator × per-second rate = overflow risk on long time periods

# Withdrawal queue multi-field invariant
grep -rn "\.queued\b\|\.claimable\b\|\.claimed\b" src/ --include="*.sol"
# claimed <= claimable <= queued must hold — check all update paths

# Cross-chain signature reuse
grep -rn "keccak256.*abi\.encodePacked\|ECDSA\.recover" src/ --include="*.sol"
grep -rn "chainId\|block\.chainid" src/ --include="*.sol"
# ecrecover WITHOUT chainId = same sig valid on all chains

# try/catch DoS liveness
grep -rn "} catch" src/ --include="*.sol" -A5 | grep -B1 "revert\|IncompatibleAdapter"

# Nullifier timing (Worldcoin-style)
grep -rn "nullifiers\[.*\] = true\|nullifierUsed\[" src/ --include="*.sol" -B5
# Marked before action = frontrun can permanently DoS identity

---

SPECIFIC BUG PATTERN SEARCHES

Silent Modifier (if vs require)

# Find modifiers that use if() without revert — silently does nothing for unauthorized callers
grep -rn "modifier only" src/ --include="*.sol" -A10 | grep -A10 "if ("
# Correct: require(condition, "msg"); _;
# BUG: if (condition) { _; }  ← no else = still executes for unauthorized

Tautology Check (variable compared to itself)

grep -rn "require(" src/ --include="*.sol" | grep "\b\(\w\+\) == \1\b"
# e.g. require(a == a, ...) = always true → always passes

Same-Role Count Mismatch

grep -rn "onlyRole\b" src/ --include="*.sol" | wc -l
grep -rn "grantRole(" src/ --include="*.sol" | wc -l
# More onlyRole uses than grantRole calls = some roles may never be granted

Accounting: Balance vs Tracked

grep -rn "balanceOf(address(this))" src/ --include="*.sol"
grep -rn "totalDeposited\|totalPrincipal\|_balance\b" src/ --include="*.sol"
# If protocol uses raw balanceOf for pricing AND has separate totalDeposited
# → donation attack: send tokens directly to contract → inflates balance

---

→ NEXT: 04-poc-and-foundry.md