What changed
OWASP refreshed its Smart Contract Top 10 for 2026 as a forward looking list. Categories run SC01 through SC10. Each entry links to a short guide on the OWASP Smart Contract Security site. The project sits under the broader OWASP SCS program.
OWASP states the ranking uses 2025 incident and survey data to forecast 2026 risk focus. It is an awareness doc, not a replacement for formal audits. Teams can pair it with the SCWE list and public checklists on the same site.
SC01 covers access control flaws. SC02 covers business logic errors. SC03 covers price oracle abuse. SC04 covers flash loan chains. SC05 covers missing input checks. SC06 covers unsafe external calls. SC07 covers arithmetic mistakes. SC08 covers reentrancy. SC09 covers integer overflow style bugs. SC10 covers proxy and upgrade mistakes.
Why it matters
Protocol teams need a shared vocabulary for pre launch reviews. Regulators and insurers increasingly ask for mapped controls. A public Top 10 gives security leads a slide ready frame that is vendor neutral.
Forward looking labels mean some items rank higher than older lists even if exploit counts vary by chain. Treat order as guidance, not as a guarantee of your next breach type.
Who is affected
Smart contract auditors, protocol founders, and DeFi product managers. Bridge and L2 teams that ship upgradeable proxies. Enterprise Web3 pilots that must show OWASP aligned testing to banks.
What to do next
Walk your codebase against SC01 access paths and SC10 upgrade hooks first. Map each finding to the OWASP page and your internal ticket system. Add the SCS checklist pass before mainnet upgrades.
What to watch
Image: GitHub
OWASP edits to individual SC pages after new high profile exploits. Companion docs on Web3 attack vectors beyond contracts. Audit firms publishing coverage maps tied to SC01 to SC10.
How to use the 2026 list in practice
Start with roles and funds flow, not syntax alone. SC02 business logic bugs often hide in reward math that passes unit tests. SC03 oracle issues show up when pools use thin liquidity pairs as price feeds.
SC04 flash loan items remind teams that atomic loans amplify logic bugs. SC05 and SC06 overlap with classic Solidity lint rules but still miss custom call paths. SC07 and SC09 shrink on modern compiler defaults yet stay relevant on cross chain ports.
SC10 proxy issues spike when teams ship fast upgrade keys without timelocks. Pair the Top 10 read with your incident retros from the last year. Mark which SC tags would have caught each past bug.
Training junior devs on SC labels beats ad hoc Twitter threads. Link each internal playbooks section to one OWASP URL for quick refreshers.
Image: GitHub
Limits of the document
OWASP does not rank chains or tokens. It does not replace formal verification. Some categories overlap; one exploit may tag SC03, SC04, and SC06 at once. Use tags to organize fixes, not to argue priority theater.
Schedule a brown bag where devs read one SC page each week. Ten short sessions beat one rushed audit crunch before launch.
Add SC IDs to pull request templates so reviewers know which risk class a diff touches. Access control diffs should cite SC01 every time.
Keep a living map from your past incidents to SC codes. That map makes the Top 10 feel real to new hires.
Share the live OWASP site link in your audit kickoff deck. Clients trust neutral lists more than vendor PDFs alone.
When you fix SC10 proxy bugs, record who holds upgrade keys and timelock delays. Auditors ask every time.
Add SC tags to your bug bounty rules so hunters know which classes earn bonuses. Clear rules reduce noisy reports.
Sources
- Primary — OWASP, Smart Contract Top 10 project README (2026). Defines the forward looking 2026 list and SC01 to SC10 links.
- Primary — OWASP SCS, Smart Contract Top 10 live site (2026). Publishes reader facing SC01 through SC10 pages.
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