OWASP just dropped the Smart Contract Top 10 for 2025, and if you’re building anything in Web3, this update isn’t something you can afford to skim.OWASP Smart Contract Top 10 2025, Smart contract attacks aren’t slowing down, and the new list reflects exactly how today’s exploits are happening — not how they used to.
This year’s revision leans heavily on real attack data collected from multiple sources, including SolidityScan’s Web3HackHub, which tracks actual incidents across the ecosystem. In other words, this isn’t theory. It’s a snapshot of what attackers are doing right now.
The OWASP Smart Contract Top 10 (2025)
OWASP groups the most critical smart contract risks into ten categories. These aren’t random — they’re the vulnerabilities that keep showing up in audits, hacks, and post-mortems.
| Code | Vulnerability Name | What It Means |
|---|---|---|
| SC01:2025 | Access Control Vulnerabilities | Missing or weak permission checks that let outsiders do things they shouldn’t. |
| SC02:2025 | Price Oracle Manipulation | Attackers trick the contract by feeding it manipulated external price data. |
| SC03:2025 | Logic Errors | Bugs in the business logic that make the contract behave in ways you didn’t intend. |
| SC04:2025 | Lack of Input Validation | Contracts trusting whatever input they receive — a big mistake. |
| SC05:2025 | Reentrancy Attacks | The classic exploit where an attacker re-enters a function before it finishes, often draining funds. |
| SC06:2025 | Unchecked External Calls | Contracts calling outside code without checking whether things worked. |
| SC07:2025 | Flash Loan Attacks | Using massive temporary liquidity to manipulate markets or protocol state in one transaction. |
| SC08:2025 | Integer Overflow & Underflow | Math errors caused by fixed-size integers, often leading to messed-up balances. |
| SC09:2025 | Insecure Randomness | “Random” values that aren’t actually random — easy pickings for attackers. |
| SC10:2025 | Denial of Service (DoS) | Making a contract unusable by exhausting resources or forcing constant reverts. |
What’s Actually New Compared to 2023
The landscape changed quite a bit since the 2023 list. A few shifts stand out:
1. Reentrancy isn’t going anywhere
Despite years of people preaching about it, we still see high-value exploits because someone forgot a check or reused unsafe patterns.
2. Flash loan attacks now officially matter
They were once considered niche. Now they’re a mainstream attack method in DeFi, so OWASP gave them their own dedicated category.
3. Access control issues remain the biggest problem
Still the #1 cause of multi-million dollar losses. Most hacks don’t require fancy techniques — just missing permissions.
4. Oracle manipulation moves up
As DeFi grows, oracle dependencies grow with it. Attackers go after the inputs instead of the contracts themselves.
The Numbers Tell the Real Story
According to Web3HackHub’s 2024 data:
- Total losses: $1.42 billion
- Number of incidents: 149
- Most damaging categories:
- Access control
- Flash loan exploits
- Oracle manipulation
- Reentrancy
If you zoom out, the pattern is obvious: attackers don’t need exotic techniques. They just exploit the same mistakes developers keep repeating.
Why You Should Care
Smart contracts don’t have the luxury of patching after deployment. Once your code hits the chain, every bug is a potential payout for attackers.
This updated OWASP list matters for:
- Developers trying to avoid catastrophic logic bugs
- Founders who need to prove their protocols are secure
- Auditors who want a modern framework for risk classification
- DeFi teams handling billions in liquidity
- Security researchers tracking exploit trends
If you’re still designing security around older versions of this list, you’re already behind. Attackers evolve faster than documentation.
Final thoughts
The OWASP Smart Contract Top 10 for 2025 reflects what’s actually happening in the wild. The biggest threats now revolve around access control, price manipulation, unchecked external interactions, and the growing sophistication of flash loan-based attacks.
If you’re working in Web3, treat this list as a mandatory checklist — not an optional best practice.
