CVE-2026-54052 n8n-MCP: Cross-tenant access to workflow version backups in multi-tenant HTTP deployments
Authenticated tenants can read and delete other tenants' workflow backups in multi-tenant HTTP deployments due to missing isolation.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-54052?
CVE-2026-54052 is a critical missing authorization vulnerability in czlonkowski n8n-mcp, published on 15 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
n8n-MCP is an MCP server that provides AI assistants access to n8n node documentation, properties, and operations. Prior to 2.56.1, in HTTP mode with multi-tenancy enabled through ENABLE_MULTI_TENANT=true, n8n-mcp's local workflow version history backups were not isolated per tenant, allowing an authenticated tenant to read workflow version snapshots belonging to other tenants and delete or destroy other tenants' stored backups, including full node definitions, credential references, and authorization headers. This issue is fixed in version 2.56.1.
Which versions are affected by CVE-2026-54052?
2 open source packages ship an affected version, including n8n-mcp. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
n8n-mcp npm | All versions | 2.56.1 |
n8n-mcp npm | All versions | 2.56.1 |
Products include N8n-Mcp N8n-Mcp.
How do I fix CVE-2026-54052?
Upgrade n8n-mcp to 2.56.1 or later.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-54052 being exploited?
There is no known exploitation of CVE-2026-54052 in the wild and no public exploit code.
Other vulnerabilities in czlonkowski n8n-mcp
- CVE-2026-42449 n8n-MCP: IPv4-mapped IPv6 addresses bypass SSRF protection in validateUrlSync(), enabling full SSRF for SDK embedders
- CVE-2026-39974 n8n-MCP has an Authenticated SSRF via instance-URL header in multi-tenant HTTP mode
- CVE-2026-45707 n8n-MCP: Multi-tenant MCP requests fall back to process-level n8n credentials when tenant headers are absent or incomplete
- CVE-2026-44694 n8n-MCP: Authenticated SSRF in n8n-mcp webhook and API client paths
- CVE-2026-45582 n8n-MCP: Workflow telemetry sanitizer could retain partial values from URL-shaped node parameters
Sources
Also known as GHSA-j6r7-6fhx-77wx.