VULNERABILITY INTELLIGENCE
CVE-2026-67430
CVSS score5.3 MEDIUM
EPSS probability0.37%
CISA KEVNot currently listed
Published2026-07-29
Last modified2026-10-24
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Description
MCP Ruby SDK is the official Ruby SDK for Model Context Protocol servers and clients. Prior to 0.23.0, MCP::Server::Transports::StreamableHTTPTransport in the mcp gem does not expire sessions by default, so repeated initialize requests retain unbounded ServerSession objects and can exhaust process memory. This issue is fixed in version 0.23.0.
Weakness classification
- security-advisories@github.com: CWE-401