CVE-2026-21877 — Vulnerability in n8n — CVE Details

CRITICAL

n8n Vulnerable to RCE via Arbitrary File Write

Published January 6, 2026Updated February 3, 2026Source: osv

Summary

### Impact n8n is affected by an authenticated Remote Code Execution (RCE) vulnerability. Under certain conditions, an authenticated user may be able to cause untrusted code to be executed by the n8n service. This could result in full compromise of the affected instance. Both self-hosted and n8n Cloud instances are impacted. ### Patches The issue has been resolved in n8n version 1.121.3. Users are advised to upgrade to this version or later to fully address the vulnerability. ### Workarounds If upgrading is not immediately possible, administrators can reduce exposure by disabling the Git node and limiting access for untrusted users. ### References - n8n documentation: [Blocking access to nodes](https://docs.n8n.io/hosting/securing/blocking-nodes/)

Advisory Timeline

First published January 6, 2026 (279 days ago).
Last revised February 3, 2026 — 27 days after initial publication.

Remediation

Upgrade to the fixed version using your package manager.

npm

Update n8n to 1.121.3 or later

npm install n8n@1.121.3

After upgrading, run your dependency scanner again to confirm the vulnerability is resolved.

Affected Packages (1)

Affects 1 ecosystem: npm (1).

Package	Ecosystem	Affected	Fixed In
n8n	npm	All versions	1.121.3

Vulnerability Classification

Common Weakness Enumeration (CWE) identifiers for this vulnerability type.

CWE-434
Unrestricted File UploadMITRE

CVSS Score Breakdown

What the CVSS (Common Vulnerability Scoring System) 9.9 score means for each attack dimension.

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Changed

Confidentiality

High

Integrity

High

Availability

High

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

References

Frequently Asked Questions

What is CVE-2026-21877?: n8n Vulnerable to RCE via Arbitrary File Write This vulnerability has been assigned a severity rating of CRITICAL (CVSS score: 9.9/10).
How do I check if my project is affected by CVE-2026-21877?: CVE-2026-21877 affects n8n. Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2026-21877 and 200,000+ other known vulnerabilities.

Severity & Exploitability

CVSS Score

9.9

Exploitation is straightforward and causes maximum impact. Patch immediately.

Also Known As

GHSA-v364-rw7m-3263

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