cvedb.io
CVE-2025-6515
MEDIUM · CVSS 6.8
EPSS exploitation probability: 0%
Published 2025-10-20T17:15:39.197 · Last modified 2026-06-17T10:02:03.383

Summary

The MCP SSE endpoint in oatpp-mcp returns an instance pointer as the session ID, which is not unique nor cryptographically secure. This allows network attackers with access to the oatpp-mcp server to guess future session IDs and hijack legitimate client MCP sessions, returning malicious responses from the oatpp-mcp server.

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.