CVE-2026-56356 json
n8n - Stored Cross-Site Scripting in Chat Trigger Node Custom CSS Field
published 7mo ago modified 13d ago also GHSA-3c7f-5hgj-h279 , EUVD-2026-40444
- cvss
- 5.4
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 16%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- npm n8n 1.123.27, 2.13.3, 2.14.1
- n8n n8n 1.123.27, 2.13.3, 2.14.1
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 4mo ago
Exploit prediction
0.25% chance of exploitation in the next 30 days, higher than 16% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.1 | 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 |
| CNA | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
| CNA | 4.0 | 5.1 | 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| GitHub | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | n8n | <1.123.27 >=2.14.0, <2.14.1 >=2.0.0-rc.0, <2.13.3 |
1.123.27 2.14.1 2.13.3 |
Affected products
- n8n n8n
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/n8n-io/n8n/security/advisories/GHSA-3c7f-5hgj-h279
vendor-advisory, web, mitigation
-
vulncheck.com
/advisories/n8n-stored-cross-site-scripting-in-chat-trigger-node-custom-css-field
third-party-advisory
-
github.com
/n8n-io/n8n
package
Sources
- CVE List CVE-2026-56356
- GitHub Advisory GHSA-3c7f-5hgj-h279
- NVD CVE-2026-56356
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.