CVE-2026-63118

MediumCVSS 6.9/10Last modified Oct 24, 2026

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.

Metrics

CVSS 4.0 6.9/10CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Weakness enumeration

CWE-346CWE-350

Affected software

No affected versions have been published.

Timeline

Published
Jul 29, 2026
Last modified
Oct 24, 2026
NVD status
Deferred

Related CVEs from 2026

CVE-2026-631196.2MCP Ruby SDK is the official Ruby SDK for Model Context Protocol servers and clients. Prior to 0.23.0, MCP::Server::Transports::StdioTranspoCVE-2026-63123.1Insufficient policy enforcement in Passwords in Google Chrome prior to 147.0.7727.101 allowed a remote attacker who had compromised the rendCVE-2026-631208.4pghoard is a PostgreSQL backup daemon and restore tooling that stores backup data in cloud object stores. Prior to version 2.7.2, an incomplCVE-2026-631236.5Tina is a headless content management system. Prior to 2.5.2, the TinaCMS CLI package's Vite dev server packages/@tinacms/cli/src/next/vite/CVE-2026-631259.9Incus is a system container and virtual machine manager. Prior to version 7.3.0, an unprivileged, project-confined Incus user (a non-admin TCVE-2026-631267.5Wire provides gRPC and protocol buffers for Android, Kotlin, Swift, and Java. Prior to 6.4.5 and 7.0.0-alpha04, Wire protobuf readers do notCVE-2026-631278.2RMCP is an official Rust SDK for the Model Context Protocol. Prior to 2.0.0, the rmcp crate's OAuth implementation in crates/rmcp/src/transpCVE-2026-631287.5RMCP is an official Rust SDK for the Model Context Protocol. Prior to 2.0.0, the rmcp crate's stateful Streamable HTTP server in crates/rmcpCVE-2026-63133.1Insufficient policy enforcement in CORS in Google Chrome prior to 147.0.7727.101 allowed a remote attacker who had compromised the renderer CVE-2026-631305.5EspoCRM is an open source customer relationship management application. Prior to 9.3.10, an authenticated administrator can provide crafted CVE-2026-631316.0OpenBao is an open source identity-based secrets management system. Prior to 2.6.0, OpenBao's vault/policy/acl.go could evaluate a broader wCVE-2026-631329.2OpenBao is an open source identity-based secrets management system. Prior to 2.6.0, OpenBao's handleLogicalRecovery path in http/logical.go