Kimi cli: FastMCP updated to MCP 1.23+ due to CVE-2025-66416
FastMCP versions prior to 2.14.0 allowed usage of MCP SDK versions earlier than 1.23, which are vulnerable to CVE-2025-66416. FastMCP itself does not directly use the affected MCP SDK components. Users should upgrade to FastMCP 2.14.0 or later to avoid exposure to this vulnerability.
AI Analysis
Technical Summary
CVE-2025-66416 affects MCP SDK versions prior to 1.23. While FastMCP does not directly use the vulnerable MCP SDK components, versions of FastMCP before 2.14.0 permitted the use of MCP SDK versions older than 1.23, thus potentially exposing users to the vulnerability. The issue is mitigated by upgrading FastMCP to version 2.14.0 or later, which requires MCP SDK 1.23 or newer.
Potential Impact
Users running FastMCP versions before 2.14.0 who use MCP SDK versions older than 1.23 may be exposed to the vulnerability identified as CVE-2025-66416. FastMCP itself is not directly vulnerable, but the dependency on older MCP SDK versions introduces risk.
Mitigation Recommendations
Upgrade FastMCP to version 2.14.0 or later, which enforces usage of MCP SDK version 1.23 or newer, thereby mitigating the vulnerability. Since a patch is available and recommended, users should apply this upgrade promptly.
Kimi cli: FastMCP updated to MCP 1.23+ due to CVE-2025-66416
Description
FastMCP versions prior to 2.14.0 allowed usage of MCP SDK versions earlier than 1.23, which are vulnerable to CVE-2025-66416. FastMCP itself does not directly use the affected MCP SDK components. Users should upgrade to FastMCP 2.14.0 or later to avoid exposure to this vulnerability.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2025-66416 affects MCP SDK versions prior to 1.23. While FastMCP does not directly use the vulnerable MCP SDK components, versions of FastMCP before 2.14.0 permitted the use of MCP SDK versions older than 1.23, thus potentially exposing users to the vulnerability. The issue is mitigated by upgrading FastMCP to version 2.14.0 or later, which requires MCP SDK 1.23 or newer.
Potential Impact
Users running FastMCP versions before 2.14.0 who use MCP SDK versions older than 1.23 may be exposed to the vulnerability identified as CVE-2025-66416. FastMCP itself is not directly vulnerable, but the dependency on older MCP SDK versions introduces risk.
Mitigation Recommendations
Upgrade FastMCP to version 2.14.0 or later, which enforces usage of MCP SDK version 1.23 or newer, thereby mitigating the vulnerability. Since a patch is available and recommended, users should apply this upgrade promptly.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- BREW-kimi-cli-GHSA-rcfx-77hg-w2wv
- Osv Schema Version
- 1.7.3
- Ecosystems
- ["Homebrew"]
Threat ID: 6aac8e0b55bf5e2cf54903d1
Added to database: 09/18/2026, 01:04:11 UTC
Last enriched: 09/18/2026, 01:33:46 UTC
Last updated: 09/18/2026, 03:01:24 UTC
Views: 4
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