CVE-2025-6515 (GCVE-0-2025-6515)
Vulnerability from cvelistv5 – Published: 2025-10-20 16:13 – Updated: 2025-10-20 16:33
VLAI
EPSS
VEX
Title
Reuse of session IDs in oatpp-mcp leads to session hijacking and prompt hijacking by remote attackers
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.
Severity
6.8 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-10-20 16:33 UTC
CWE
- CWE-330 - Use of Insufficiently Random Values
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://research.jfrog.com/vulnerabilities/oatpp-… | third-party-advisory |
Impacted products
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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