GHSA-hx4h-vr3m-45vh
n8n: Prototype Pollution via VM Expression Engine Sandbox Escape Leads to Denial of Service
Blast Radius
Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.
n8nnpmDescription
Impact
An authenticated user able to create or edit a workflow expression could abuse the expression engine's array-element access to obtain a reference to a host built-in and pollute its prototype in the main n8n process, leading to a denial of service.
Both self-hosted and cloud instances running the VM expression engine are affected.
Patches
The issue has been fixed in n8n versions 1.123.67, 2.31.5, and 2.32.1. Users should upgrade to one of these versions or later to remediate the vulnerability.
Workarounds
If upgrading is not immediately possible, administrators should consider the following temporary mitigations:
- Restrict n8n instance access to fully trusted users only.
- Disable the VM expression engine if an alternative is available for your deployment.
These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | n8n | all versions | 1.123.67 |
| 📦npm | n8n | ≥ 2.32.0&&< 2.32.1 | 2.32.1 |
| 📦npm | n8n | ≥ 2.0.0-rc.0&&< 2.31.5 | 2.31.5 |
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 1.123.67 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-hx4h-vr3m-45vh 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 GHSA-hx4h-vr3m-45vh 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 GHSA-hx4h-vr3m-45vh. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-hx4h-vr3m-45vh in your dependencies?
O3 detects GHSA-hx4h-vr3m-45vh across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.