CVE-2026-65591
n8n before 1.123.64 Sanitizer Bypass Remote Code Execution
Blast Radius
n8n📦n8n📦n8nReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects npm packages — download data is not available via public APIs for these ecosystems.
Description
n8n contains a sanitizer bypass vulnerability in the legacy expression evaluator's computed-member handler. An authenticated user with workflow create or modify permissions can craft a malicious expression to bypass the sanitizer and achieve host-level code execution as the n8n process. The legacy expression engine is the default in affected versions. Fixed in n8n 1.123.64, 2.29.8, and 2.30.1.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | n8n | all versions | 1.123.64 |
| 📦npm | n8n | ≥ 2.30.0&&< 2.30.1 | 2.30.1 |
| 📦npm | n8n | ≥ 2.0.0-rc.0&&< 2.29.8 | 2.29.8 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for n8n. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update n8n to 1.123.64 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-65591 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-65591 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-65591. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-65591 in your dependencies?
O3 detects CVE-2026-65591 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.