XSS in N8n
CVE-2026-77072
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.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N.
EPSS exploit prediction
EPSS: 0.003 (21.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 21st percentile — 21.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001
Affected products
- N8n — versions 2.34.0
- N8n-Io N8n
Weakness classification (CWE)
References
- github.com/n8n-io/n8n/security/advisories/GHSA-rmr5-775f-jvm2 (vendor-advisory, Mitigation, Vendor Advisory)
- www.vulncheck.com/advisories/n8n-before-stored-xss-via-form-completion-page (Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2026-77072?
- CVE-2026-77072 is a high-severity vulnerability in N8n, classified under Cross-site Scripting. CVSS score: 7.6/10. Published 2026-08-20.
- How severe is CVE-2026-77072?
- High severity. CVSS v3 base score is 7.6 out of 10.