FastMCP is the standard framework for building MCP applications. Prior to version 2.14.2, the server does not properly respect the resource parameter submitted by the client in the authorization and token request. Instead of issuing the token explicitly for the MCP server, the token is issued for the base_url passed to the OAuthProxy during initialization. This issue has been patched 2.14.2.
Advisories
Source ID Title
Github GHSA Github GHSA GHSA-5h2m-4q8j-pqpj FastMCP OAuth Proxy token reuse across MCP servers
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Wed, 18 Mar 2026 15:15:00 +0000

Type Values Removed Values Added
CPEs cpe:2.3:a:jlowin:fastmcp:*:*:*:*:*:*:*:*
Metrics cvssV3_1

{'score': 7.4, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N'}

cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N'}


Wed, 18 Mar 2026 00:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-1220
References
Metrics threat_severity

None

cvssV3_1

{'score': 7.4, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N'}

threat_severity

Important


Tue, 17 Mar 2026 10:00:00 +0000

Type Values Removed Values Added
First Time appeared Jlowin
Jlowin fastmcp
Vendors & Products Jlowin
Jlowin fastmcp

Mon, 16 Mar 2026 19:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Mon, 16 Mar 2026 18:45:00 +0000

Type Values Removed Values Added
Description FastMCP is the standard framework for building MCP applications. Prior to version 2.14.2, the server does not properly respect the resource parameter submitted by the client in the authorization and token request. Instead of issuing the token explicitly for the MCP server, the token is issued for the base_url passed to the OAuthProxy during initialization. This issue has been patched 2.14.2.
Title FastMCP OAuth Proxy token reuse across MCP servers
Weaknesses CWE-863
References
Metrics cvssV4_0

{'score': 7.4, 'vector': 'CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-03-16T19:09:43.436Z

Reserved: 2025-12-29T14:34:16.261Z

Link: CVE-2025-69196

cve-icon Vulnrichment

Updated: 2026-03-16T19:09:36.408Z

cve-icon NVD

Status : Analyzed

Published: 2026-03-16T19:16:14.397

Modified: 2026-03-18T15:11:04.733

Link: CVE-2025-69196

cve-icon Redhat

Severity : Important

Publid Date: 2026-03-16T18:07:06Z

Links: CVE-2025-69196 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-03-17T09:52:20Z

Weaknesses