Hub/AI Security/Advisories/GHSA-3qhf-m339-9g5v
MCP SDK FastMCP Server Validation Error Leading to Denial of Service
MCP Python SDK security advisory.
| GHSA | GHSA-3qhf-m339-9g5v |
|---|---|
| Published | Jul 4, 2025 |
| Severity | High 8.7 |
| CVE | CVE-2025-53366 |
| Status | patched |
| Affected | < 1.9.4 |
| Fixed in | 1.9.4 |
| Component | MCP Python SDK |
Sources
Checked 2026-11-04. We copy severity and fix versions from the source and never estimate them.
Affected tools
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