quillshield_skills

Token-efficient smart contract security auditing via Behavioral State Analysis (BSA). Scopes analysis to contract type, runs only relevant threat engines, and uses tiered output depth. Use for auditing smart contracts, security reviews, or DeFi threat modeling.

Blue-team release-gate analysis for smart contract deployment and upgrade readiness. Classifies repositories, checks deploy/upgrade execution paths, CI/CD trust boundaries, config drift, secrets/signer operational security, and outputs evidence-backed release verdicts.

Detects Denial of Service and griefing vulnerabilities in smart contracts. Covers unbounded loop DoS, block gas limit exhaustion, external call failure DoS, insufficient gas griefing (63/64 rule), storage bloat attacks, timestamp griefing, self-destruct force-feeding, and push vs pull payment pattern analysis. Use when auditing contracts with batch operations, loops over user data, reward distribution, dividend systems, or any logic that depends on address(this).balance or iterates over growing collections.

Detects unsafe external call patterns and token integration vulnerabilities in smart contracts. Covers unchecked call/delegatecall/staticcall return values, fee-on-transfer tokens, rebasing tokens, tokens with missing return values (USDT), ERC-777 callback risks, unsafe approve race conditions, return data bombs, gas stipend limitations, and push vs pull payment patterns. Use when auditing contracts that interact with external contracts, integrate arbitrary ERC20 tokens, distribute payments, or make low-level calls.

Detects input validation failures and arithmetic vulnerabilities in smart contracts. Covers missing zero-address and zero-amount checks, division-before-multiplication precision loss, rounding direction exploitation, ERC4626 vault share inflation attacks, unsafe integer casting, dust amount exploitation, and Solidity 0.8+ unchecked block edge cases. Use when auditing contracts with fee calculations, share pricing, exchange rates, unchecked blocks, or any public-facing functions that accept user input.

Detects price oracle manipulation and flash loan attack vectors in DeFi smart contracts. Classifies oracle trust models (Chainlink, TWAP, spot price, custom), identifies stale price risks, circular price dependencies, and flash loan atomicity exploitation patterns. Use when auditing DeFi protocols that depend on price data, oracle integrations, lending protocols, DEXs, derivatives, or any contract where flash loans could manipulate state within a single transaction.

Detects vulnerabilities in upgradeable proxy smart contracts including storage layout collisions, uninitialized implementations, function selector clashing, delegatecall context issues, and upgrade path safety. Covers Transparent Proxy, UUPS (EIP-1822), Beacon, Diamond (EIP-2535), and Minimal Proxy (EIP-1167) patterns. Use when auditing upgradeable contracts, reviewing implementation upgrades, analyzing delegatecall architectures, or verifying proxy pattern compliance.

Systematically detects all reentrancy vulnerability variants in smart contracts — classic, cross-function, cross-contract, and read-only reentrancy. Builds call graphs, verifies CEI (Checks-Effects-Interactions) pattern compliance, traces state changes relative to external calls, and identifies callback vectors through ERC-777/ERC-1155 hooks. Use when auditing contracts that make external calls, transfer ETH or tokens, interact with callback-enabled standards, or have complex multi-contract architectures.

Detects logic vulnerabilities in smart contracts by analyzing guard-state consistency patterns. Identifies functions that bypass security checks (require, modifiers) that other functions consistently apply. Uses the Consistency Principle — a contract is its own specification. Use when auditing smart contracts for missing access controls, inconsistent pause checks, logic bugs, forgotten modifiers, or when traditional tools report no issues but logic errors may exist.

Detects signature replay vulnerabilities in smart contracts — affecting 19.63% of signature-using contracts. Covers five replay types (same-chain, cross-chain, cross-contract, nonce-skip, expired-signature), EIP-712 domain separator verification, nonce management analysis, ecrecover edge cases (address(0), malleability, s-value), permit/permit2 safety, ERC-1271 contract wallet support, and meta-transaction security. Use when auditing contracts with ecrecover, ECDSA, EIP-712, permit, meta-transactions, multi-sig, or any off-chain signature verification.

Detects broken mathematical relationships between state variables in smart contracts. Automatically infers invariants (totalSupply = sum(balances), conservation laws, ratio constraints) then finds functions that violate them. Catches unauthorized minting, broken tokenomics, accounting desynchronization, and state drift. Use when auditing for state-state invariant violations, broken accounting, supply mismatches, desynchronized state variables, or conservation law violations in smart contracts.