Open-Source Security Intelligence

Know every vulnerability
before it knows you.

DevGuard continuously monitors your dependencies and alerts you when CVEs like this one affect your stack — with real-time threat intelligence built for developers.

Search

GHSA-f3rg-xqjj-cj9w

MediumCVSS 6.5 / 10
Published May 18, 2026·Last modified May 18, 2026
Affected Components(0)

No affected components available

Description

Summary

In affected versions of n8n-mcp, the workflow telemetry sanitizer could retain partial fragments of URL-shaped node parameters before sending workflow data to the project's anonymous telemetry backend. Values placed in HTTP-Request-style node parameters — such as customer or tenant identifiers, short secrets embedded in query strings, and signed request parameters — could therefore appear in stored telemetry, contrary to the collection boundary documented in PRIVACY.md.

Impact

Operators with access to the project's telemetry backend could read partial fragments of workflow URL parameters that should not have been collected. The bug was scoped to URL-shaped fields in workflow definitions; credentials, OAuth tokens, and workflow execution data are not affected — credentials are removed by a separate code path, and long secrets and known-provider tokens are matched by dedicated patterns.

Patches

Fixed in n8n-mcp 2.51.3. Upgrading is the recommended remediation.

Workarounds

For users who cannot upgrade immediately, disable anonymous telemetry by setting any of these environment variables to true:

  • N8N_MCP_TELEMETRY_DISABLED
  • TELEMETRY_DISABLED
  • DISABLE_TELEMETRY

Credit

Reported by @u-ktdi.

Risk Scores
Base Score
6.5

The vulnerability can be exploited over the network without needing physical access. It is easy for an attacker to exploit this vulnerability. An attacker needs basic access or low-level privileges. No user interaction is needed for the attacker to exploit this vulnerability. The impact is confined to the system where the vulnerability exists. There is a high impact on the confidentiality of the information.

Threat Intelligence
6.0

Exploitation attempts have been detected. Elevated vigilance and prompt remediation are advised.

EPSS
0.26%

The exploit probability is very low. The vulnerability is unlikely to be exploited in the next 30 days.

Exploit
Not available

We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.

Browse More

Scan your project

Continuously monitor your dependencies and get alerted when vulnerabilities like this one affect your stack.

Checkout DevGuard