CVE-2026-86994: n8n Workflow Automation Information Disclosure

CVE-2026-86994 Overview

CVE-2026-86994 is a missing authorization vulnerability [CWE-862] in n8n, an open source workflow automation platform. The /rest/active-workflows endpoint returned every active workflow ID on the instance to any authenticated member, ignoring workflow sharing boundaries. Workflow activation, deactivation, and publication push events were also broadcast to clients that could not access the affected workflow. This disclosed workflow IDs, version IDs, and activation error details to unauthorized users. The issue affects the files packages/cli/src/services/active-workflows.service.ts and packages/cli/src/workflows/workflow-push-notifier.service.ts. Fixed releases are 1.123.76, 2.37.7, and 2.38.2.

Critical Impact
Any authenticated member of an n8n instance can enumerate all active workflow IDs and receive real-time activation event metadata for workflows they were never granted access to.

Affected Products

n8n versions prior to 1.123.76
n8n versions prior to 2.37.7
n8n versions prior to 2.38.2

Discovery Timeline

2026-09-08 - CVE-2026-86994 published to NVD
2026-09-09 - Last updated in NVD database

Technical Details for CVE-2026-86994

Vulnerability Analysis

The vulnerability is a broken access control issue in the n8n REST API and its push notification service. The /rest/active-workflows endpoint is intended to return workflow identifiers that the requesting user is authorized to view. Instead, the endpoint returned every active workflow ID on the instance regardless of the sharing configuration. This exposes metadata about workflows owned by other users or projects to any member of the instance.

The second component of the flaw resides in the workflow push notifier. n8n uses server-push events to inform connected clients when a workflow is activated, deactivated, or published. These events were broadcast to all connected clients rather than filtered against the recipient's access rights. Subscribed clients received workflow IDs, version IDs, and activation error details for workflows they could not otherwise access.

Root Cause

The root cause is an absent authorization check when enumerating and broadcasting workflow state. In active-workflows.service.ts, the service returns the raw list of active workflow identifiers without filtering by the caller's project or sharing scope. In workflow-push-notifier.service.ts, push events are dispatched to all subscribers without validating recipient authorization for the referenced workflow. Both paths violate least-privilege enforcement as classified by CWE-862: Missing Authorization.

Attack Vector

Exploitation requires an authenticated low-privilege member account on a vulnerable n8n instance. The attacker issues an authenticated GET request to /rest/active-workflows and receives every active workflow ID on the platform. The attacker can additionally connect to the workflow push channel and passively collect activation, deactivation, and publication events, harvesting workflow IDs, version IDs, and activation error strings for workflows owned by other tenants on the instance. No user interaction is required beyond authentication.

See the GitHub Security Advisory GHSA-65xw-2v52-jhxc for the maintainer's technical description.

Detection Methods for CVE-2026-86994

Indicators of Compromise

Unexpected authenticated GET requests to /rest/active-workflows from user accounts that do not own or share any active workflows.
Push notification subscribers receiving activation or deactivation events referencing workflow IDs outside their authorized project scope.
Access log entries showing a single member account repeatedly polling /rest/active-workflows at short intervals.

Detection Strategies

Review n8n application logs and reverse proxy logs for calls to /rest/active-workflows and correlate the requesting user against workflow ownership records.
Enable audit logging on the workflow push notifier channel and flag events delivered to sessions with no matching workflow membership.
Compare the count of workflow IDs returned to a given user against the count they are authorized to view; a mismatch indicates exploitation.

Monitoring Recommendations

Ingest n8n access and audit logs into a centralized log platform and alert on anomalous access patterns to /rest/active-workflows.
Baseline normal push notification traffic per user account and alert on volume spikes that suggest enumeration.
Track the installed n8n version across all instances and alert when any node runs a version older than 1.123.76, 2.37.7, or 2.38.2.

How to Mitigate CVE-2026-86994

Immediate Actions Required

Upgrade n8n to 1.123.76, 2.37.7, or 2.38.2 on the applicable release train as documented in the n8n release notes.
Audit which member accounts accessed /rest/active-workflows prior to patching and rotate any secrets referenced in workflow names or error messages that may have leaked.
Review member role assignments and remove accounts that do not require access to the instance.

Patch Information

The maintainers released fixed builds 1.123.76, 2.37.7, and 2.38.2. The fixes apply authorization filtering in packages/cli/src/services/active-workflows.service.ts so only workflow IDs the caller can access are returned, and in packages/cli/src/workflows/workflow-push-notifier.service.ts so push events are delivered only to authorized subscribers. Release artifacts are published at the n8n 2.37.7 release and the n8n 2.38.2 release.

Workarounds

Restrict network access to the n8n REST API and push endpoints so only trusted administrators can reach the instance until patching is complete.
Reduce the number of member accounts on the instance and move sensitive workflows to a separate, isolated n8n deployment.
Place a reverse proxy in front of n8n that blocks unauthenticated or non-administrator access to /rest/active-workflows as a temporary control.

bash

# Configuration example: verify the running n8n version and upgrade
npm ls n8n
npm install -g n8n@2.38.2
# Or for Docker deployments
docker pull n8nio/n8n:2.38.2
docker stop n8n && docker rm n8n
docker run -d --name n8n -p 5678:5678 n8nio/n8n:2.38.2