CVE-2026-33946EPSS p40.8%

CVE-2026-33946CVE-2026-33946

lfprojects / mcp_ruby_sdk

Description

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.

Scoring

CVSS 5.9 ()
VectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS0.47% probability of exploitation · percentile 40.8% · 2026-10-27T12:03:15Z
Last modified2026-10-26
Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.