Description
n8n versions before 1.123.69, 2.33.4, and 2.34.1 contain a JavaScript task runner VM sandbox escape. The runner's prototype-freezing routine covers globalThis functions but not internal module constructors such as EventEmitter, allowing an authenticated user with Code node access to exploit prototype pollution to execute arbitrary commands within the runner container. Because the polluted prototype is a process-wide object, the corruption persists across other tenants' Code node executions on the same shared runner. On v1.x instances without task runners enabled, Code node JavaScript runs directly in the main n8n process, where the impact could be higher.
Affected products
n8n: n8n
References2
- github.com/n8n-io/n8n/security/advisories/GHSA-m3hg-p5r9-fg9h MitigationVendor Advisory
- www.vulncheck.com/advisories/n8n-before-remote-code-execution-v… Third Party Advisory
Metrics
- CVSS 3.1
-
7.6
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:L - CVSS 4.0
-
7.2
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 1% percentile: 47 · as of 10 November 2026
- CWE
- CWE-94
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