CVE-2025-6515
Reuse of session IDs in oatpp-mcp leads to session hijacking and prompt hijacking by remote attackers
- State
- Published
- Severity
- 6.8 Medium
- Published
- Oct 20, 2025
- Updated
- Oct 20, 2025
- Reserved
- Jun 23, 2025
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 6.8 Medium | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:H | JFROG |
Weaknesses
- CWE-330 Use of Insufficiently Random Values
Affected Products
| Product | Versions |
|---|---|
oatpp-mcpoatpp |
|
References
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