VULNERABILITY INTELLIGENCE
CVE-2025-6515
CVSS score6.8 MEDIUM
EPSS probability0.40%
CISA KEVNot currently listed
Published2025-10-20
Last modified2026-10-08
CVSS vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:H
Description
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.
Weakness classification
- reefs@jfrog.com: CWE-330