CVE-2025-6515 - Vulnerability Details - OpenCVE

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.

No CVSS v4.0

Attack Vector Network

Attack Complexity High

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact High

Availability Impact High

User Interaction Required

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable no

Technical Impact total

No data.

No data.

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References

Link	Providers
https://research.jfrog.com/vulnerabilities/oatpp-mcp-prompt-hijacking-jfsa-2025-001494691/

History

Mon, 20 Oct 2025 20:00:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

Mon, 20 Oct 2025 16:30:00 +0000

Type	Values Removed	Values Added
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.
Title		Reuse of session IDs in oatpp-mcp leads to session hijacking and prompt hijacking by remote attackers
Weaknesses		CWE-330
References		https://research.jfrog.com/vulnerabilities/oatpp-mcp-prompt-hijacking-jfsa-2025-001494691/
Metrics		cvssV3_1 `{'score': 6.8, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:H'}`

MITRE

Status: PUBLISHED

Assigner: JFROG

Published: 2025-10-20T16:13:43.527Z

Updated: 2025-10-20T16:33:47.787Z

Reserved: 2025-06-23T10:56:07.978Z

Link: CVE-2025-6515

Vulnrichment

Updated: 2025-10-20T16:33:44.469Z

NVD

Status : Received

Published: 2025-10-20T17:15:39.197

Modified: 2025-10-20T17:15:39.197

Link: CVE-2025-6515

Redhat

No data.

OpenCVE Enrichment

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