SEPTEMBER 19, 2026
Live Feed
Back to database
Case File

CVE-2026-63118

MEDIUM · CVSS 6.9 EPSS 0.19% Public Exploit

Source: NVD + CISA KEV + EPSS · Published 2026-07-29 · Last synced 2026-08-28

CyberRota Analysis

AI-Generated

The MCP Ruby SDK prior to version 0.23.0 is vulnerable due to the lack of validation for HTTP Host or Origin request headers in the MCP::Server::Transports::StreamableHTTPTransport component. This flaw allows attackers to exploit DNS rebinding techniques, potentially enabling unauthorized access to locally running MCP servers and the invocation of exposed tools. Organizations using this SDK should prioritize upgrading to version 0.23.0 to mitigate the risk of such attacks.

Public Exploit Signal

A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.

GitHub PoC Links
github.com ↗ github.com ↗ github.com ↗

Note: these links are listed for security research and verification purposes only.

CVE
CVE-2026-63118
Severity
MEDIUM
CVSS
6.9
EPSS
0.19%

Original NVD 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.