CVE-2026-21858 — Vulnerability in n8n — CVE Details

CRITICAL

n8n Vulnerable to Unauthenticated File Access via Improper Webhook Request Handling

Published January 7, 2026Updated February 3, 2026Source: osv

Summary

### Impact A vulnerability in n8n allows an attacker to access files on the underlying server through execution of certain form-based workflows. A vulnerable workflow could grant access to an unauthenticated remote attacker. This could result in exposure of sensitive information stored on the system and may enable further compromise depending on deployment configuration and workflow usage. ### Patches The issue has been fixed in n8n version 1.121.0. Users should upgrade to this version or later to remediate the vulnerability. ### Workarounds No official workarounds are available. As a temporary mitigation, users may restrict or disable publicly accessible webhook and form endpoints until upgrading.

Advisory Timeline

First published January 7, 2026 (278 days ago).
Last revised February 3, 2026 — 26 days after initial publication.

Remediation

Upgrade to the fixed version using your package manager.

npm

Update n8n to 1.121.0 or later

npm install n8n@1.121.0

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	1.121.0

Vulnerability Classification

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

CWE-20
Improper Input ValidationMITRE

CVSS Score Breakdown

What the CVSS (Common Vulnerability Scoring System) 10.0 score means for each attack dimension.

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Changed

Confidentiality

High

Integrity

High

Availability

None

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

References

Frequently Asked Questions

What is CVE-2026-21858?: n8n Vulnerable to Unauthenticated File Access via Improper Webhook Request Handling This vulnerability has been assigned a severity rating of CRITICAL (CVSS score: 10.0/10).
How do I check if my project is affected by CVE-2026-21858?: CVE-2026-21858 affects n8n. Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2026-21858 and 200,000+ other known vulnerabilities.

Severity & Exploitability

CVSS Score

10.0

Exploitation is straightforward and causes maximum impact. Patch immediately.

Also Known As

GHSA-v4pr-fm98-w9pg

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