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CVE-2025-6515
Good to know:
Date: October 20, 2025
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.
Severity Score
Severity Score
Weakness Type (CWE)
Use of Insufficiently Random Values
CWE-330CVSS v3.1
| Base Score: |
|
|---|---|
| Attack Vector (AV): | NETWORK |
| Attack Complexity (AC): | HIGH |
| Privileges Required (PR): | NONE |
| User Interaction (UI): | REQUIRED |
| Scope (S): | UNCHANGED |
| Confidentiality (C): | NONE |
| Integrity (I): | HIGH |
| Availability (A): | HIGH |