CVE-2026-25054: n8n: XSS enables session hijacking
MEDIUMn8n is widely used to orchestrate AI agent workflows and stores credentials for LLM APIs, databases, and third-party services. An attacker with any workflow editor role can inject XSS payloads into markdown fields (sticky notes, descriptions) that execute when privileged users open the workflow, enabling full session hijack and credential exfiltration from n8n's credential vault. Patch immediately to 1.123.9 or 2.2.1 and audit who holds workflow create/modify permissions — treat this as a credential exposure risk, not just a web bug.
Risk Assessment
Effective risk is higher than the 5.4 CVSS suggests for AI-heavy environments. n8n is a trust hub: it stores API keys for OpenAI, Anthropic, vector databases, and downstream services. A session hijack against an admin account gives an attacker full access to all stored credentials, workflow logic, and connected systems. The low-privilege requirement and low attack complexity mean any disgruntled or compromised contributor can weaponize this. Not in KEV but the credential pivot potential makes this HIGH priority for teams running AI agent pipelines on n8n.
Affected Systems
| Package | Ecosystem | Vulnerable Range | Patched |
|---|---|---|---|
| n8n | npm | — | No patch |
Do you use n8n? You're affected.
Severity & Risk
Attack Surface
Recommended Action
6 steps-
PATCH
Upgrade to n8n 1.123.9 (v1 branch) or 2.2.1 (v2 branch) immediately.
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RESTRICT
Enforce least-privilege on workflow create/modify permissions — only trusted users should be able to author workflows.
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AUDIT
Review all workflows for unexpected sticky notes, HTML/script content in markdown fields, or recently modified workflow descriptions.
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ROTATE
Treat all credentials stored in n8n as potentially compromised if unpatched instances were accessible by untrusted users. Rotate LLM API keys, database passwords, and webhook secrets.
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DETECT
Alert on unusual n8n admin session activity, new credential additions, or webhook modifications from unexpected IPs.
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ISOLATE
For self-hosted deployments, restrict n8n UI access to VPN/internal network.
CISA SSVC Assessment
Source: CISA Vulnrichment (SSVC v2.0). Decision based on the CISA Coordinator decision tree.
Classification
Compliance Impact
This CVE is relevant to:
Frequently Asked Questions
What is CVE-2026-25054?
n8n is widely used to orchestrate AI agent workflows and stores credentials for LLM APIs, databases, and third-party services. An attacker with any workflow editor role can inject XSS payloads into markdown fields (sticky notes, descriptions) that execute when privileged users open the workflow, enabling full session hijack and credential exfiltration from n8n's credential vault. Patch immediately to 1.123.9 or 2.2.1 and audit who holds workflow create/modify permissions — treat this as a credential exposure risk, not just a web bug.
Is CVE-2026-25054 actively exploited?
No confirmed active exploitation of CVE-2026-25054 has been reported, but organizations should still patch proactively.
How to fix CVE-2026-25054?
1. PATCH: Upgrade to n8n 1.123.9 (v1 branch) or 2.2.1 (v2 branch) immediately. 2. RESTRICT: Enforce least-privilege on workflow create/modify permissions — only trusted users should be able to author workflows. 3. AUDIT: Review all workflows for unexpected sticky notes, HTML/script content in markdown fields, or recently modified workflow descriptions. 4. ROTATE: Treat all credentials stored in n8n as potentially compromised if unpatched instances were accessible by untrusted users. Rotate LLM API keys, database passwords, and webhook secrets. 5. DETECT: Alert on unusual n8n admin session activity, new credential additions, or webhook modifications from unexpected IPs. 6. ISOLATE: For self-hosted deployments, restrict n8n UI access to VPN/internal network.
What systems are affected by CVE-2026-25054?
This vulnerability affects the following AI/ML architecture patterns: agent frameworks, API integrations, RAG pipelines, workflow orchestration.
What is the CVSS score for CVE-2026-25054?
CVE-2026-25054 has a CVSS v3.1 base score of 5.4 (MEDIUM). The EPSS exploitation probability is 0.01%.
Technical Details
NVD Description
n8n is an open source workflow automation platform. Prior to versions 1.123.9 and 2.2.1, a Cross-Site Scripting (XSS) vulnerability existed in a markdown rendering component used in n8n's interface, including workflow sticky notes and other areas that support markdown content. An authenticated user with permission to create or modify workflows could abuse this to execute scripts with same-origin privileges when other users interact with a maliciously crafted workflow. This could lead to session hijacking and account takeover. This issue has been patched in versions 1.123.9 and 2.2.1.
Exploitation Scenario
An attacker with a low-privilege n8n account (e.g., a contractor or shared team account) creates a workflow and embeds a JavaScript payload in a sticky note using a markdown rendering bypass. The payload exfiltrates the victim's session cookie to an attacker-controlled endpoint. An admin or senior developer opens the workflow for review — standard collaborative behavior. The script executes in their browser with same-origin privileges, sends the session token to the attacker, who then authenticates as the admin. The attacker navigates to n8n Credentials, exports all stored secrets (OpenAI API key, Pinecone token, Postgres credentials), and modifies existing AI agent workflows to include data exfiltration nodes or malicious tool call injections. The compromise of the AI pipeline is silent and persistent until the workflow modification is noticed.
Weaknesses (CWE)
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N References
Timeline
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Same package: n8n
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