CVE-2026-77077

Published Aug 20, 2026

Last updated 3 days ago

Overview

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.
Source
disclosure@vulncheck.com
NVD status
Received

Risk scores

CVSS 4.0

Type
Secondary
Base score
7.2
Impact score
-
Exploitability score
-
Vector string
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
Severity
HIGH

Weaknesses

disclosure@vulncheck.com
CWE-94

Social media

Hype score
Not currently trending