Description
n8n before 1.123.69, 2.33.4, and 2.34.1 contains a stored cross-site scripting vulnerability in the Form node's completion page. The completion page applied its sandboxing Content-Security-Policy only when respondWith was not set to 'redirect', but responseText was always rendered as raw HTML. An authenticated member could set respondWith to 'redirect' via an expression while keeping responseText populated, causing the completion page to serve unsanitized HTML and script from the n8n origin. Any visitor who submitted the resulting public form would have that script execute same-origin with their session.
Affected products
n8n: n8n
References2
- github.com/n8n-io/n8n/security/advisories/GHSA-rmr5-775f-jvm2 MitigationVendor Advisory
- www.vulncheck.com/advisories/n8n-before-stored-xss-via-form-com… Third Party Advisory
Metrics
- CVSS 3.1
-
7.6
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N - CVSS 4.0
-
8.4
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/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 - EPSS — exploit probability
- 0% percentile: 24 · as of 10 November 2026
- CWE
- CWE-79
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