n8n Vulnerable to Stored XSS through Attachments View EndpointGHSA-c8hm-hr8h-5xjw
MEDIUMFix: n8n-io/n8n#14350GHSA-c8hm-hr8h-5xjw is a medium-severity (CVSS 5) Cross-site Scripting (XSS) vulnerability in n8n. A fix is available for n8n — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-c8hm-hr8h-5xjw.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
n8nnpmDescription
n8n is a workflow automation platform. Prior to version 1.90.0, n8n is vulnerable to stored cross-site scripting (XSS) through the attachments view endpoint. n8n workflows can store and serve binary files, which are accessible to authenticated users. However, there is no restriction on the MIME type of uploaded files, and the MIME type could be controlled via a GET parameter. This allows the server to respond with any MIME type, potentially enabling malicious content to be interpreted and executed by the browser. An authenticated attacker with member-level permissions could exploit this by uploading a crafted HTML file containing malicious JavaScript. When another user visits the binary data endpoint with the MIME type set to text/html, the script executes in the context of the user’s session. This script could send a request to change the user’s email address in their account settings, effectively enabling account takeover. This issue has been patched in version 1.90.0.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | n8n | all versions | 1.90.0npm install n8n@1.90.0 |
Affected Products
n8nn8nDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for n8n, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update n8n to 1.90.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-c8hm-hr8h-5xjw is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.
Frequently Asked Questions
Is GHSA-c8hm-hr8h-5xjw in your dependencies?
Find it across npm, including transitive dependencies.