Cross-site scripting in n8n - CVE-2026-33749
Published: April 23, 2026
Vulnerability identifier: #VU127206
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-33749
CWE-ID: CWE-79
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: n8n
Affected software:
n8n
n8n
Detailed vulnerability description
The vulnerability allows a remote user to execute arbitrary JavaScript in a victim's authenticated session.
The vulnerability exists due to cross-site scripting in the /rest/binary-data endpoint when serving an HTML binary data object without a filename inline in the browser. A remote user can craft a workflow that produces the malicious binary data object and send the resulting URL to a victim to execute arbitrary JavaScript in a victim's authenticated session.
User interaction is required, and exploitation requires permission to create or modify workflows.
How to mitigate CVE-2026-33749
Install security update from vendor's website.