How broadly exploitable is this vulnerability?

Exploitability depends on how workflows are configured and exposed. If a vulnerable workflow is reachable over the network and does not require authentication, a remote attacker could exploit it without credentials. In more restricted deployments, exploitation may require authenticated access or specific roles.

What level of access does an attacker need to take advantage of this issue?

An attacker needs the ability to interact with a vulnerable form-based workflow on the affected n8n instance. In some setups this may require only network access, while in others it may require authenticated access to the n8n UI or APIs that trigger those workflows.

What is the safest general fix pattern for affected workflows?

The safest pattern is to eliminate direct use of user input in file operations. Replace user-controlled paths with fixed identifiers or strictly validated, limited choices, and ensure file access is constrained to predefined directories or resources that do not contain sensitive information.

Severity:

CRITICAL RISK

(10.0)

Improper Input Validation (CWE-20) Enabling File Access via Workflows in n8n Automation Platform

CVE-2026-21858

Published:

Jan 7, 2026

Status:

Analyzed

Summary

Affected Context

Exploit Preconditions

Why This Happens

Potential Impact

General Mitigation Guidance

How Teams Detect Issues Like This

Frequently Asked Questions

Source

NDV

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CRITICAL RISK

CRITICAL

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Account Takeover / Loss of Account Control

February 17, 2026

CWE-77;CWE-78

HIGH RISK

HIGH

(7.3)

OS Command Injection (CWE-78) in node-sonos-http-api TTS Provider for macOS

Remote Code Execution on the Server Host

February 17, 2026

Vulnerability Type

Category:

Improper Input Validation

CWE:

CWE-20

Impact:

Unauthorized File Access / Information Disclosure

Severity:

CRITICAL RISK

(10.0)

CVSS Version:

3.1

Vulnerability Type

Category:

Improper Input Validation

CWE:

CWE-20

Impact:

Unauthorized File Access / Information Disclosure

Severity:

CRITICAL RISK

(10.0)

CVSS Version:

3.1

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Improper Input Validation (CWE-20) Enabling File Access via Workflows in n8n Automation Platform

Summary

Affected Context

Exploit Preconditions

Why This Happens

Potential Impact

General Mitigation Guidance

How Teams Detect Issues Like This

Frequently Asked Questions

Source

Recent Vulnerabilities

CRITICAL RISK

CRITICAL

(9.8)

Missing Authentication for Forgot-Password Email Change API (CWE-306)

HIGH RISK

HIGH

(7.3)

OS Command Injection (CWE-78) in node-sonos-http-api TTS Provider for macOS

Vulnerability Type

Vulnerability Type

Vulnerability Type

Vulnerability Type

Catch This CVE While Code Is Being Written

Ship clean & secure code faster

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