Cross-site scripting in n8n - #VU127209
Published: April 23, 2026
Vulnerability identifier: #VU127209
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: N/A
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 script in a victim's browser.
The vulnerability exists due to improper neutralization of input during web page generation in the Chat Trigger node Custom CSS field when rendering the public chat page. A remote user can inject malicious JavaScript into the Custom CSS field to execute arbitrary script in a victim's browser.
User interaction is required, as a victim must visit the chat URL.
Remediation
Install security update from vendor's website.