CVE-2026-33946
MCP Ruby SDK
- Severity
- Medium
- Published
- March 27, 2026
- Last modified
- June 17, 2026
MCP Ruby SDK is the official Ruby SDK for Model Context Protocol servers and clients. Prior to version 0.9.2, the Ruby SDK's streamable_http_transport.rb implementation contains a session hijacking vulnerability. An attacker who obtains a valid session ID can completely hijack the victim's Server-Sent Events (SSE) stream and intercept all real-time data. Version 0.9.2 contains a patch.
CVSS vector CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Weakness
References
- github.comPatch
- github.comPatch
- github.comPatch
- github.comPatch
- github.comPatch
- github.comRelease Notes
- github.comExploitVendor Advisory
- hackerone.com
Listed in
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