CVE-2026-54303: n8n Reflected XSS in Meta & Teams Triggers (v2.24.0 Fix)

Technical summary

The vulnerability exists in the Meta and Microsoft Teams trigger node endpoints, which fail to sanitize user-supplied query parameters before reflecting them in HTTP responses. An attacker crafts a URL containing malicious JavaScript within a query parameter, then tricks a logged-in n8n user into visiting it. Without input validation or output encoding, the JavaScript executes in the user's browser with the privileges of the n8n application. The absence of restrictive Content-Security-Policy headers further eliminates a secondary defense mechanism. This is a classic reflected XSS (CWE-79) scenario where the payload traverses the network on each request rather than being stored server-side.

Business impact

Successful exploitation allows attackers to impersonate authenticated users, steal session tokens or API credentials, modify or delete workflows without audit trails, access sensitive data flowing through automation processes, or redirect users to phishing pages. For organizations using n8n to orchestrate critical business processes—such as financial data integration, customer onboarding, or internal system synchronization—compromise of user sessions could disrupt operational continuity or expose regulated data. The attack requires user interaction (clicking a link), which may limit mass-scale exploitation but increases risk in targeted spear-phishing campaigns.

Affected systems

n8n versions prior to 2.24.0 are vulnerable. The issue is specific to the Meta and Microsoft Teams trigger nodes, meaning deployments using only other trigger types are not affected by this particular endpoint flaw. Both self-hosted and cloud-deployed instances of n8n are vulnerable if running unpatched versions. Open source users, commercial license holders, and free tier users on n8n Cloud are all in scope.

Exploitability

Exploitability is straightforward: an attacker constructs a phishing URL and sends it to a known n8n user. If that user is logged into n8n and clicks the link, malicious JavaScript runs immediately in their session context. No authentication bypass, no complex tricks, and no need for special network position. However, the attack does require user interaction and prior knowledge that the target uses n8n, which moderates the overall risk. The CVSS score of 5.4 (MEDIUM) reflects this balance: network-accessible, low complexity, but dependent on user action and limited to information disclosure and integrity impacts without availability or confidentiality at system level.

Remediation

Upgrade n8n to version 2.24.0 or later immediately. This release patches the endpoint to sanitize query parameters and implements Content-Security-Policy headers to prevent inline script execution. After patching, verify that the Meta and Microsoft Teams trigger nodes function correctly in your workflows. No configuration changes are required; the fix is applied automatically upon upgrade. Organizations should prioritize patching in environments where external users might be socially engineered into clicking untrusted links.

Patch guidance

For self-hosted deployments: update your n8n installation to version 2.24.0 using your standard deployment mechanism (Docker, npm, package manager, or source build). Test the upgrade in a non-production environment first to ensure compatibility with any custom nodes or integrations. For n8n Cloud users: updates are deployed automatically by n8n; verify that your account is running 2.24.0 or later via the application settings or admin panel. After upgrade, confirm that workflows using Meta and Microsoft Teams triggers continue to function and that no manual workflow adjustments are needed.

Detection guidance

Monitor HTTP access logs for suspicious query parameters in requests to Meta and Microsoft Teams trigger node endpoints (typically paths containing 'meta' or 'teams' in the URI). Look for encoded or obfuscated JavaScript payloads, script tags, or event handlers in query strings. Check browser console logs and developer tools on user machines for XSS attempts. Web Application Firewalls (WAF) can be configured to block requests containing common XSS patterns in query parameters. Implement Content-Security-Policy headers across your n8n deployment to log and prevent inline script execution even if input validation is bypassed. Audit user account activity logs for unusual session tokens, workflow changes, or API access patterns that may indicate compromised sessions.

Why prioritize this

Although the CVSS score is MEDIUM (5.4) and the vulnerability is not listed on CISA's Known Exploited Vulnerabilities catalog, this should be prioritized for prompt patching because XSS vulnerabilities targeting authenticated users are reliable attack vectors in spear-phishing campaigns. The fix is simple and non-disruptive (upgrade to 2.24.0), and the vulnerability directly impacts session security for users of a workflow automation platform that may handle sensitive integrations. The confluence of straightforward exploitability, social engineering potential, and the business-critical nature of workflow automation warrants prioritization in patch management schedules even at MEDIUM severity.

Risk score, explained

The CVSS 3.1 score of 5.4 reflects a network-accessible vulnerability requiring low attack complexity and user interaction (PR=L, UI=R). Impacts are limited to confidentiality and integrity of the user's session and data visible to that session (C:L, I:L), with no system-wide availability impact (A:N). The scope is changed (S:C) because the vulnerability affects resources outside the vulnerable component itself—the attacker can influence the n8n application's behavior from the user's perspective. This MEDIUM rating does not capture the reputational and operational risk of a workflow automation platform being compromised; it reflects only the technical bounds of XSS impact per the CVSS methodology. Organizations should evaluate their own risk tolerance based on the criticality of n8n to their operations.

Frequently asked questions