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2026-04-30 openzeppelin migration v5 solidity ownable ecdsa messagehashutils counters reentrancyguard audit 2026

OpenZeppelin v4 vs v5 Migration: 7 API Changes That Break Your Contracts

OpenZeppelin Contracts v5 was a deliberate API redesign — many widely-used helpers were renamed, moved, or removed entirely. This guide walks through the seven changes most likely to break a contract or its audit, with before/after code for each.

2026-04-30 solady eip-7702 account abstraction erc-4337 erc-7821 proxy security migration 2026

Solady 0.1.x: EIP-7702 Proxy and What Account Abstraction Developers Need to Know

Solady 0.1.x introduces EIP7702Proxy, ERC7821, and a redesigned account-abstraction stack. This is what changed since 0.0.x, why EIP-7702 reshapes wallet architecture, and the security pitfalls to watch when migrating.

2026-04-30 ai patch generation solidity openzeppelin compile verification llm developer tools 2026

Verified Patch Generation: Why AI-Suggested Solidity Fixes Fail to Compile (and How to Fix It)

AI-generated Solidity patches look perfect — until you paste them into your codebase and watch solc reject the imports. Here is why LLMs hallucinate dependency versions, and the two-layer defense (Detect-and-Match + Verify-Compile) that actually delivers PR-ready fixes.

2026-04-25 airdrop merkle tree solidity security token distribution replay attack 2026

Airdrop Contract Security: Merkle Proof, Sybil Attacks, and Replay Vulnerabilities

Why airdrop contracts are a favorite target for exploits — merkle tree collisions, unchecked double-claiming, cross-chain replay attacks, and the secure patterns that prevent millions in losses.

2026-04-18 chainlink oracle price feed sequencer l2 min answer solidity security

Chainlink Oracle Edge Cases: Sequencer Uptime, Min/Max Answer, and Price Feed Pitfalls

Beyond stale prices, Chainlink oracles have subtle edge cases that break DeFi protocols: L2 sequencer downtime, min/max answer circuit breakers, decimal mismatch, and more. Six vulnerability classes with defensive integration patterns.

2026-04-18 reentrancy cross-contract read-only reentrancy solidity defi flashloan 2026

Cross-Contract Reentrancy and Read-Only Reentrancy: The Subtle Attack Pattern

Classic reentrancy guards miss indirect reentry through other contracts and state-read attacks during reentrant execution. Curve Finance lost millions when read-only functions returned stale prices during a reentrant call.

2026-04-18 erc-4626 vault inflation attack share price defi rounding solidity security

ERC-4626 Vault Security: Inflation Attacks, Share Price Manipulation, and Rounding Errors

ERC-4626 tokenized vaults standardized DeFi yield positions but introduced a new attack surface. Six vulnerability classes — vault inflation attacks, share price manipulation via donations, rounding direction bugs, first depositor exploits, and fee-on-transfer token incompatibility.

2026-04-17 defi exploits hacks 2025 smart contract security reentrancy access control bridge 2026

DeFi Exploits 2025: Year in Review — Smart Contract Hacks and Lessons

The major DeFi smart contract exploits of 2025 — root causes, amounts lost, and what each hack reveals about the vulnerability classes that keep draining protocols.

2026-04-15 solidity security permit eip-2612 signature-replay defi eip-712 phishing 2026

EIP-2612 Permit() and Signature Replay Attacks: The Hidden Risk in Modern DeFi Tokens

How permit() gasless approvals enable signature replay attacks, phishing, and frontrunning in DeFi. Real exploit patterns, vulnerable code, and detection strategies.

2026-04-15 solidity security checklist mainnet audit smart-contract best-practices 2026

Solidity Security Checklist: 10 Vulnerabilities to Fix Before Mainnet Deployment

A practical pre-deployment security checklist for Solidity developers. Covering reentrancy, access control, integer overflow, oracle manipulation, and more — with detection tips for each.

2026-04-15 solidity vulnerabilities security access-control oracle flash-loan slither mythril semgrep

Top 5 Solidity Vulnerabilities and How to Detect Them Automatically

An analysis of the five vulnerability patterns responsible for 90% of DeFi exploits, with code examples and automated detection methods for each.

2026-04-13 defi security business-logic hack smart-contract 2026 audit

Business Logic Flaws: The Silent Killer of DeFi Security in 2026

Analyzing AlkemiEarn and SynapLogic cases to understand the risks of business logic vulnerabilities and strategies for prevention using multi-engine security scanning.

2026-04-09 mythx smart contract security roadmap AI security multi-chain solidity rust developer tools 2026

Beyond MythX: Where Smart Contract Security Is Heading in 2026

MythX is gone. The security tooling landscape is shifting toward multi-engine scanning, AI-powered analysis, and developer workflow integration. Here's what's changing and what ContractScan is building next.

2026-04-09 solidity smart contract security cross-chain bridge bridge exploit Wormhole Ronin Nomad multichain audit DeFi security

Cross-Chain Bridge Security: Why Bridges Are the Biggest Target in 2026

Cross-chain bridges have lost over $2.5 billion to exploits — more than any other DeFi category. Understanding what keeps going wrong, and what the better-designed bridges do differently, is essential for anyone building or auditing cross-chain infrastructure.

2026-04-09 solidity smart contract security MEV front-running sandwich attack flashbots DeFi security audit mempool

Front-Running and MEV: What Solidity Developers Need to Know

MEV bots extract hundreds of millions from DeFi every year by targeting patterns that look completely normal in smart contract code. Here's how front-running works, where it comes from, and what you can actually do about it.

2026-04-09 solidity smart contract security integer overflow SafeMath arithmetic audit solidity 0.8 unchecked type casting

Integer Overflow in Solidity 0.8+: Are We Really Safe?

Solidity 0.8 added built-in overflow protection, and most developers moved on. But overflow-related bugs didn't disappear — they evolved. Here's where they still hide.

2026-04-09 solidity smart contract security oracle manipulation chainlink TWAP flash loan DeFi security audit price feed

Oracle Manipulation Attacks: Chainlink vs TWAP vs Custom Feeds

Price oracle manipulation is behind billions in DeFi losses. Understanding how each oracle type can be gamed — and what makes one harder to attack than another — is essential for anyone building or auditing DeFi protocols.

2026-04-09 solidity smart contract security proxy pattern upgradeable contracts UUPS transparent proxy diamond proxy EIP-2535 audit vulnerability

Proxy Pattern Vulnerabilities: UUPS, Transparent, and Diamond

Upgradeable contracts solve the immutability problem but introduce a new class of subtle, high-severity bugs. Here's what actually goes wrong with UUPS, Transparent, and Diamond proxies — and how to catch them before deployment.

2026-04-02 drift hack security 2026 oracle reentrancy defi

Drift Protocol Hack and Q1 2026: What Builders Need to Know

A breakdown of the Drift Protocol exploit, Q1 2026 hack trends, and what smart contract developers can do to protect their code.

2026-04-01 mythx mythx alternative mythx shutdown mythx migration smart contract security solidity security scanning

MythX Has Shut Down: Your Migration Guide to ContractScan

MythX (ConsenSys Diligence) shut down in 2023. If you still have pipelines referencing the MythX API or CLI, here's how to migrate to ContractScan — free, fast, and no sign-up required.

2026-04-01 Slither Mythril Semgrep security-tools static-analysis smart-contract

Free Smart Contract Security Tools Compared: Slither vs Mythril vs Semgrep

A hands-on comparison of Slither, Mythril, and Semgrep — the three leading open-source security tools — covering detection scope, speed, and usability.

2026-03-25 CI/CD automation DevSecOps smart-contract security API

Automating Smart Contract Security Scans in Your CI/CD Pipeline

A complete guide to automating Solidity contract security scanning in your CI/CD pipeline. Detect vulnerabilities on every PR and block deployments on critical findings.

2026-03-25 security solidity defi vulnerabilities

Top 5 Solidity Vulnerabilities in 2026

A deep-dive into the most exploited smart contract vulnerabilities of 2025 and 2026, with real-world examples and prevention strategies.

2026-03-22 reentrancy smart-contract-security solidity defi-security vulnerability

Reentrancy: From The DAO to Euler Finance

The most notorious smart contract vulnerability in history. Analyzing how reentrancy attacks evolved from the 2016 DAO hack to Euler Finance in 2023, and how to defend against them.

2026-03-18 threat-intelligence defi-security risk-feed smart-contract-security automation

How ContractScan Tracks the Latest DeFi Hacks

ContractScan automatically collects DeFi hack incidents and vulnerability data every week. Learn how our live threat intelligence system uses Rekt.news, DeFiHackLabs, and the SWC Registry to keep your scans up to date.

2026-03-15 flash-loan smart-contract-security solidity defi-security price-manipulation

Flash Loan Attacks: A Complete Breakdown

Analyzing the mechanics of flash loan attacks through the bZx, PancakeBunny, and Euler Finance cases, with price oracle manipulation defense patterns.

2026-03-11 access-control smart-contract-security solidity defi-security vulnerability

How Access Control Mistakes Led to $1.4B in Losses

Access control vulnerabilities rank #1 in smart contract security losses as of 2025. Analyzing the Poly Network, Ronin Bridge, and Nomad Bridge cases — totaling over $1.4B — with defense patterns.

2026-03-08 security smart-contract solidity blockchain introduction

Introduction to Smart Contract Security: Why It Matters

Smart contracts are immutable once deployed. Learn why security must be a core part of development, illustrated with real-world hack case studies.

2025-01-20 audit checklist security best-practices

Smart Contract Security Audit Checklist

A practical pre-deployment checklist covering access control, arithmetic, external calls, oracle safety, and more.

2024-12-03 reentrancy security exploit defi

Anatomy of a DeFi Hack: Reentrancy Deep Dive

Step-by-step breakdown of how reentrancy exploits work, illustrated with a real attack flow and countermeasures.