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 v3
6.8
EPSS
0.0004
EPSS Percentile
12.5%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:H
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
total
Details
CWE
CWE-330
Status
published
Products (1)
oatpp/oatpp-mcp
Published
Oct 20, 2025
Tracked Since
Feb 18, 2026