CVE-2025-6515 — Reuse of session IDs in oatpp-mcp leads to session hijacking and prompt hijacking by remote attackers
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 t…
Published: 2025-10-20 · CVSS: 6.8 · CVSS 3.1
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7