Which versions of N8n are affected by CVE-2026-33749?

Organizations using n8n should be aware of moderate risk from CVE-2026-33749, a cross-site scripting vulnerability rated CVSS 6.3.. A patch is available.

How to fix or mitigate CVE-2026-33749?

Within 30 days: Identify affected systems and apply vendor patches as part of regular patch cycle. Verify Content-Security-Policy and output encoding.

N8n CVE-2026-33749

Q: What is the CVSS score of CVE-2026-33749?

CVE-2026-33749 has a CVSS 4.0 base score of 6.3 (Medium). CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:L/VI:L/VA:N/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. EPSS exploitation probability: 0.0%.

EUVD-2026-15956 MEDIUM

Cross-site Scripting (XSS) (CWE-79)

2026-03-25 GitHub_M

GHSA-qfc3-hm4j-7q77

XSS Privilege Escalation N8n

6.3

CVSS 4.0 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

6.3 MEDIUM

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:L/VI:L/VA:N/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:L/VI:L/VA:N/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

Scope

Lifecycle Timeline

Patch released

Mar 31, 2026 - 21:13 nvd

Patch available

EUVD ID Assigned

Mar 25, 2026 - 19:02 euvd

EUVD-2026-15956

Analysis Generated

Mar 25, 2026 - 19:02 vuln.today

CVE Published

Mar 25, 2026 - 18:39 nvd

MEDIUM 6.3

DescriptionGitHub Advisory

n8n is an open source workflow automation platform. Prior to versions 1.123.27, 2.13.3, and 2.14.1, an authenticated user with permission to create or modify workflows could craft a workflow that produces an HTML binary data object without a filename. The /rest/binary-data endpoint served such responses inline on the n8n origin without Content-Disposition or Content-Security-Policy headers, allowing the HTML to render in the browser with full same-origin JavaScript access. By sending the resulting URL to a higher-privileged user, an attacker could execute JavaScript in the victim's authenticated session, enabling exfiltration of workflows and credentials, modification of workflows, or privilege escalation to admin. The issue has been fixed in n8n versions 1.123.27, 2.13.3, and 2.14.1. Users should upgrade to one of these versions or later to remediate the vulnerability. If upgrading is not immediately possible, administrators should consider the following temporary mitigations: Limit workflow creation and editing permissions to fully trusted users only, and/or restrict network access to the n8n instance to prevent untrusted users from accessing binary data URLs. These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.

AnalysisAI

A stored cross-site scripting (XSS) vulnerability in n8n workflow automation platform allows authenticated users to craft malicious workflows that execute arbitrary JavaScript in the browsers of higher-privileged users. Affected versions are n8n prior to 1.123.27, 2.13.3, and 2.14.1 (identified via CPE cpe:2.3:a:n8n-io:n8n). An attacker with workflow creation/modification permissions can exploit the /rest/binary-data endpoint's failure to properly sanitize HTML responses, enabling credential theft, workflow manipulation, and privilege escalation to administrative access with full same-origin context.

Technical ContextAI

The vulnerability stems from improper output encoding and missing security headers in the binary data serving mechanism of n8n (CWE-79: Improper Neutralization of Input During Web Page Generation). The /rest/binary-data endpoint serves user-controlled HTML content without the Content-Disposition header (which would force download) and without Content-Security-Policy headers (which would restrict JavaScript execution). This allows HTML payloads embedded in workflow binary objects to render inline in the user's authenticated browser session with full JavaScript access to the n8n origin, enabling DOM-based and reflected XSS attacks that persist through workflow storage.

RemediationAI

Immediately upgrade to n8n version 1.123.27, 2.13.3, or 2.14.1 or later, depending on which branch your installation uses; consult https://github.com/n8n-io/n8n/security/advisories/GHSA-qfc3-hm4j-7q77 for release notes and upgrade procedures. Until patching is completed, implement short-term mitigations: restrict workflow creation and editing permissions to fully trusted users only, enforce network-level access controls to limit exposure of the n8n instance to untrusted users, and consider serving n8n behind a reverse proxy configured to add Content-Security-Policy: default-src 'self' and Content-Disposition: attachment headers to all /rest/binary-data responses. These workarounds significantly reduce but do not fully eliminate risk and should not replace patch deployment.