CVE-2026-45707
n8n-MCP: Multi-tenant MCP requests fall back to process-level n8n credentials when tenant headers are absent or incomplete
Description
n8n-MCP is an MCP server that provides AI assistants access to n8n node documentation, properties, and operations. Prior to 2.51.2, when ENABLE_MULTI_TENANT=true, the HTTP transport documents that the target n8n instance is selected per-request from x-n8n-url / x-n8n-key headers. Requests that omitted those headers — or supplied only one of them — silently fell back to the process-level N8N_API_URL / N8N_API_KEY credentials configured for the operator's own n8n instance. As a result, an authenticated MCP tenant could cause n8n management calls to execute against the operator's instance instead of its own. This affects HTTP-mode deployments of n8n-mcp that are run as a shared multi-tenant service. Single-tenant deployments (ENABLE_MULTI_TENANT unset or false) are not affected. This vulnerability is fixed in 2.51.2.
INFO
Published Date :
May 29, 2026, 2:16 p.m.
Last Modified :
May 29, 2026, 2:16 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-45707
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update n8n-MCP to version 2.51.2.
- Ensure ENABLE_MULTI_TENANT is configured correctly.
- Verify HTTP transport header usage.
- Review operator and tenant credential configurations.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-45707.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-45707 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-45707
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-45707 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-45707 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by [email protected]
May. 29, 2026
Action Type Old Value New Value Added Description n8n-MCP is an MCP server that provides AI assistants access to n8n node documentation, properties, and operations. Prior to 2.51.2, when ENABLE_MULTI_TENANT=true, the HTTP transport documents that the target n8n instance is selected per-request from x-n8n-url / x-n8n-key headers. Requests that omitted those headers — or supplied only one of them — silently fell back to the process-level N8N_API_URL / N8N_API_KEY credentials configured for the operator's own n8n instance. As a result, an authenticated MCP tenant could cause n8n management calls to execute against the operator's instance instead of its own. This affects HTTP-mode deployments of n8n-mcp that are run as a shared multi-tenant service. Single-tenant deployments (ENABLE_MULTI_TENANT unset or false) are not affected. This vulnerability is fixed in 2.51.2. Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N Added CWE CWE-284 Added Reference https://github.com/czlonkowski/n8n-mcp/commit/853015d0897be7cf2d9d4726de195c938e4395ab Added Reference https://github.com/czlonkowski/n8n-mcp/releases/tag/v2.51.2 Added Reference https://github.com/czlonkowski/n8n-mcp/security/advisories/GHSA-jxx9-px88-pj69