Vulnerability in Modelcontextprotocol Ruby-sdk

CVE-2026-67431

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 bind a session ID to a session owner, allowing an attacker with…

Affected products

Weakness classification (CWE)

References