CVE-2026-118679
Deferred Deferred - Pending Action

Server-Side Request Forgery in n8n Slack Trigger Webhook

Publication date: 2026-10-28

Last updated on: 2026-10-28

Assigner: VulnCheck

Description
n8n before 1.123.83, 2.41.4, and 2.42.1 contains a server-side request forgery vulnerability in the Slack Trigger webhook that allows unauthenticated attackers to exfiltrate Slack tokens by bypassing signature verification when no signing secret is set. Attackers who know the webhook URL can name a file to download, causing the node to send the workspace access token to an attacker host and return the response.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published
2026-10-28
Last Modified
2026-10-28
Generated
2026-10-28
AI Q&A
2026-10-28
EPSS Evaluated
N/A
NVD
CVE-2026-118679
EUVD
EUVD-2026-112385

Affected Vendors & Products

Showing 3 associated CPEs
Vendor Product Version / Range
n8n-io n8n 0
n8n-io n8n 2.42.0
n8n-io n8n 2.0.0

Helpful Resources

Exploitability

CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-918 The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.

Attack-Flow Graph

AI Quick Actions

Instant insights powered by AI
Executive Summary

n8n before versions 1.123.83, 2.41.4, and 2.42.1 has a server-side request forgery (SSRF) vulnerability in the Slack Trigger webhook. When no signing secret is set, unauthenticated attackers can bypass signature verification. By knowing the webhook URL, they can trick the system into sending Slack workspace access tokens to an attacker-controlled host.

Detection Guidance

To detect this vulnerability, check if your n8n instance is running a vulnerable version (before 1.123.83, 2.41.4, or 2.42.1). Inspect webhook URLs for Slack Trigger nodes and verify if signature verification is disabled. Monitor network traffic for unexpected outbound requests to external hosts from n8n.

Impact Analysis

Attackers could steal Slack workspace access tokens, gaining unauthorized access to sensitive communications and data. This could lead to data breaches, unauthorized actions in Slack, or further exploitation of connected systems using the stolen tokens.

Compliance Impact

This vulnerability could lead to unauthorized access to personal or sensitive data, violating GDPR (data protection) and HIPAA (health information privacy) requirements. Organizations may face fines, legal penalties, and reputational damage due to non-compliance.

Mitigation Strategies

Upgrade n8n to the latest patched version (1.123.83, 2.41.4, or 2.42.1 or later). Ensure Slack Trigger webhooks have signature verification enabled. If no signing secret is set, disable or restrict access to the webhook URL. Review and revoke any exposed Slack tokens.

Chat Assistant

Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-118679. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70

EPSS Chart