MCP Observatory
github not analyzable

PrefectHQ/fastmcp

github

🚀 The fast, Pythonic way to build MCP servers and clients.

maintainer
PrefectHQ
license
Apache-2.0
first seen
2026-05-22
last seen
2026-06-06
releases · 30d
4
short id
risk42/100 · heuristic grade
C elevated

Source not yet analyzed — this grade rests on attested signals (CVEs, supply-chain) only. It is a floor: reading the code could raise it, not lower it.

  • vulnerabilitiesattested+50
  • trust mitigatorsmixed−8

attestedmixed

The A–E grade is our heuristic synthesis — a "review this" prompt, not a verdict. Each factor is tagged by what backs it: attested (a verifiable record), reported (a third party's claim), or inferred (our own heuristic, e.g. permissions). See methodology.

graded 11m ago · see ecosystem CVEs →

vulnerabilities8 CVEs · grade factor +50
HIGH
Missing Consent Verification in OAuth Proxy Callback Facilitates Confused Deputy Vulnerabilities EPSS 0% CVE-2026-27124 affects ["<3.2.0"]
HIGH
SSRF & Path Traversal Vulnerability in FastMCP OpenAPI Provider EPSS 0% CVE-2026-32871 affects ["< 3.2.0"]
HIGH
FastMCP Auth Integration Allows for Confused Deputy Account Takeover affects ["< 2.13.0"]
MEDIUM
Command injection via server name in subprocess-backed install commands EPSS 0% CVE-2025-64340 affects ["<3.2.0"]
MEDIUM
Improper Resource Handling in FastMCP OAuth Proxy Enables Token Reuse Across MCP Servers EPSS 0% CVE-2025-69196 affects ["<2.14.2"]
LOW
Update to MCP 1.23+ affects ["<2.14"]
MEDIUM
Windows command injection in FastMCP Cursor installer via server_name EPSS 0% CVE-2025-62801 affects ["< 2.13.0"]
MEDIUM
Reflected XSS in client's callback page EPSS 0% CVE-2025-62800 affects ["<2.13.0"]
tool safetyall quiet

No tool-safety findings — heuristic detectors run on the compute-risk cadence; a finding appears when a tool trips a rule.

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Heuristic, inferred signals — false positives (legitimately powerful tools, forks, language ports) are expected. Treat each as "review this", not a verdict. See the ecosystem-wide picture on the security hub, or the fleet security of PrefectHQ.