CVE-2026-63118EPSS p15.7%

CVE-2026-63118CVE-2026-63118

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 validate the HTTP Host or Origin request headers, which allows a malicious browser page to use DNS rebinding to reach a locally running MCP server and invoke exposed tools. This issue is fixed in version 0.23.0.

Scoring

EPSS0.26% probability of exploitation · percentile 15.7% · 2026-10-05T12:00:23Z
Last modified2026-07-30
Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.