CVE-2025-52478: n8n: Stored XSS enables full account takeover

MEDIUM

Published August 19, 2025

CISO Take

Upgrade n8n to 1.98.2 immediately if your organization uses it for workflow automation or AI agent orchestration. An authenticated attacker with minimal privileges can plant a malicious Form Trigger that silently steals session cookies from any user who visits it, enabling persistent account takeover—including admin accounts with full access to every stored API key and external service credential. If 2FA is not enforced, compromise is silent and permanent until credentials are rotated.

What is the risk?

Despite a CVSS 5.4 (Medium) rating, the practical risk is materially higher for organizations using n8n in agentic or automation contexts. The CVSS reflects network-reachable, low-complexity exploitation requiring only low privileges and one user interaction. However, n8n instances routinely store API keys for AI model endpoints, cloud services, databases, and SaaS platforms as workflow credentials. Full ATO on an n8n admin translates directly into credential exposure across every integrated system. Organizations without enforced 2FA are at highest risk; the attack leaves no obvious trace and the session remains valid until explicitly revoked.

What systems are affected?

Package	Ecosystem	Vulnerable Range	Patched
n8n	npm	—	No patch
193.4K OpenSSF 6.6 Pushed 3d ago 55% patched ~7d to patch Full package profile →

Do you use n8n? You're affected.

How severe is it?

CVSS 3.1

5.4 / 10

EPSS

0.3%

chance of exploitation in 30 days

Higher than 26% of all CVEs

Source: EPSS v3 — FIRST.org

Exploitation Status

No known exploitation

Sophistication

Trivial

What is the attack surface?

AV Network

AC Low

PR Low

UI Required

S Changed

C Low

I Low

A None

What should I do?

7 steps

Patch immediately: upgrade n8n to >= 1.98.2. No functional workaround exists for older versions.
Enforce 2FA for all n8n users, especially admins—this significantly limits the utility of stolen session cookies for account takeover.
Audit n8n credential store post-incident: rotate all API keys, OAuth tokens, and service account passwords stored in any n8n instance that may have been targeted.
Review Form Trigger workflows: identify any active Form Trigger nodes and audit who created them and whether they contain suspicious HTML payloads.
Restrict Form Trigger creation to trusted users via n8n RBAC.
Implement a Web Application Firewall (WAF) rule blocking iframe srcdoc patterns and onerror event handlers in form submissions as a defense-in-depth layer.
Monitor n8n audit logs for unusual email/account changes, workflow modifications, or credential access from unexpected source IPs.

What does CISA's SSVC say?

Decision Track

Exploitation none

Automatable No

Technical Impact total

Source: CISA Vulnrichment (SSVC v2.0). Decision based on the CISA Coordinator decision tree.

How is it classified?

Auth Bypass Data Leakage Code Execution Agent Framework API AML.T0012 - Valid Accounts AML.T0025 - Exfiltration via Cyber Means AML.T0049 - Exploit Public-Facing Application AML.T0053 - AI Agent Tool Invocation AML.T0078 - Drive-by Compromise AML.T0083 - Credentials from AI Agent Configuration AML.T0091.000 - Application Access Token

Which compliance frameworks are affected?

This CVE is relevant to:

EU AI Act

Article 15 - Accuracy, robustness and cybersecurity Article 9 - Risk management system

ISO 42001

A.6.2.6 - Security of AI system inputs A.8.1 - Security of AI system resources and information

NIST AI RMF

GOVERN 6.1 - Policies for AI risk are established MANAGE 2.2 - Mechanisms are in place to inventory AI risks

OWASP LLM Top 10

LLM05 - Insecure Output Handling

Frequently Asked Questions

What is CVE-2025-52478?

Is CVE-2025-52478 actively exploited?

No confirmed active exploitation of CVE-2025-52478 has been reported, but organizations should still patch proactively.

How to fix CVE-2025-52478?

1. Patch immediately: upgrade n8n to >= 1.98.2. No functional workaround exists for older versions. 2. Enforce 2FA for all n8n users, especially admins—this significantly limits the utility of stolen session cookies for account takeover. 3. Audit n8n credential store post-incident: rotate all API keys, OAuth tokens, and service account passwords stored in any n8n instance that may have been targeted. 4. Review Form Trigger workflows: identify any active Form Trigger nodes and audit who created them and whether they contain suspicious HTML payloads. 5. Restrict Form Trigger creation to trusted users via n8n RBAC. 6. Implement a Web Application Firewall (WAF) rule blocking iframe srcdoc patterns and onerror event handlers in form submissions as a defense-in-depth layer. 7. Monitor n8n audit logs for unusual email/account changes, workflow modifications, or credential access from unexpected source IPs.

What systems are affected by CVE-2025-52478?

This vulnerability affects the following AI/ML architecture patterns: agent frameworks, workflow automation pipelines, API integration layers, RAG pipelines, model serving orchestration.

What is the CVSS score for CVE-2025-52478?

CVE-2025-52478 has a CVSS v3.1 base score of 5.4 (MEDIUM). The EPSS exploitation probability is 0.35%.

What is the AI security impact?

Affected AI Architectures

agent frameworksworkflow automation pipelinesAPI integration layersRAG pipelinesmodel serving orchestration

MITRE ATLAS Techniques

AML.T0012 Valid Accounts

AML.T0025 Exfiltration via Cyber Means

AML.T0049 Exploit Public-Facing Application

AML.T0053 AI Agent Tool Invocation

AML.T0078 Drive-by Compromise

AML.T0083 Credentials from AI Agent Configuration

AML.T0091.000 Application Access Token

Compliance Controls Affected

EU AI Act: Article 15, Article 9

ISO 42001: A.6.2.6, A.8.1

NIST AI RMF: GOVERN 6.1, MANAGE 2.2

OWASP LLM Top 10: LLM05

What are the technical details?

Original Advisory

n8n is a workflow automation platform. From 1.77.0 to before 1.98.2, a stored Cross-Site Scripting (XSS) vulnerability was identified in n8n, specifically in the Form Trigger node's HTML form element. An authenticated attacker can inject malicious HTML via an <iframe> with a srcdoc payload that includes arbitrary JavaScript execution. The attacker can also inject malicious Javascript by using <video> coupled <source> using an onerror event. While using iframe or a combination of video and source tag, this vulnerability allows for Account Takeover (ATO) by exfiltrating n8n-browserId and session cookies from authenticated users who visit a maliciously crafted form. Using these tokens and cookies, an attacker can impersonate the victim and change account details such as email addresses, enabling full control over the account—especially if 2FA is not enabled. Users should upgrade to version >= 1.98.2.

Exploitation Scenario

An attacker with a low-privilege n8n account (e.g., obtained via credential stuffing or insider access) creates a workflow with a Form Trigger node containing a crafted HTML form. The form embeds an iframe with a srcdoc payload executing JavaScript that reads document.cookie and the n8n-browserId value, then exfiltrates them via a fetch() call to an attacker-controlled server. The attacker shares the form URL—plausibly as a legitimate-looking data collection form—with a high-privilege user or admin (via phishing, Slack, or email). When the target opens the form in their authenticated browser session, the script fires silently and delivers the session tokens. The attacker imports the stolen cookies into their browser, assumes the victim's identity, navigates to account settings, changes the email address to one they control, and locks out the legitimate user. With admin access to n8n, the attacker then exports all stored workflow credentials—API keys for connected AI services, cloud providers, and internal databases—completing a full supply chain pivot from a single low-privilege n8n account.

Weaknesses (CWE)

CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CWE-79 — Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'): The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

[Architecture and Design] Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid [REF-1482]. Examples of libraries and frameworks that make it easier to generate properly encoded output include Microsoft's Anti-XSS library, the OWASP ESAPI Encoding module, and Apache Wicket.
[Implementation, Architecture and Design] Understand the context in which your data will be used and the encoding that will be expected. This is especially important when transmitting data between different components, or when generating outputs that can contain multiple encodings at the same time, such as web pages or multi-part mail messages. Study all expected communication protocols and data representations to determine the required encoding strategies. For any data that will be output to another web page, especially any data that was received from external inputs, use the appropriate encoding on all non-alphanumeric characters. Parts of the same output document may require different encodings, which will vary depending on whether the output is in the: etc. Note that HTML Entity Encoding is only appropriate for the HTML body. Consult the XSS Prevention Cheat Sheet [REF-724] for more details on the types of encoding and escaping that are needed. HTML body Element attributes (such as src="XYZ") URIs JavaScript sections Casca

Source: MITRE CWE corpus.