Cross-site scripting in n8n - CVE-2026-54303
Published: June 16, 2026
Vulnerability identifier: #VU134569
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-2026-54303
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 the victim's browser in the n8n origin.
The vulnerability exists due to cross-site scripting in the Meta and Microsoft Teams trigger webhook verification endpoints when handling crafted query parameters. A remote user can send a specially crafted URL to a victim to execute arbitrary script in the victim's browser in the n8n origin.
User interaction is required, and the victim must be logged in and visit a crafted URL.
How to mitigate CVE-2026-54303
Install security update from vendor's website.