CVE-2025-66414
BaseFortify
Publication date: 2025-12-02
Last updated on: 2026-03-10
Assigner: GitHub, Inc.
Description
Description
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| lfprojects | mcp_typescript_sdk | to 1.24.0 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-1188 | The product initializes or sets a resource with a default that is intended to be changed by the product's installer, administrator, or maintainer, but the default is not secure. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability exists in the MCP TypeScript SDK prior to version 1.24.0, where DNS rebinding protection is not enabled by default for HTTP-based servers. If an HTTP-based MCP server is run locally without authentication using certain transports (StreamableHTTPServerTransport or SSEServerTransport) and without enabling DNS rebinding protection, a malicious website could exploit DNS rebinding to bypass same-origin policy restrictions. This allows the attacker to send requests to the local MCP server and potentially invoke tools or access resources on behalf of the user under these limited conditions.
How can this vulnerability impact me? :
The vulnerability can allow an attacker to bypass browser same-origin policy restrictions via DNS rebinding when a local MCP HTTP server is running without authentication and without DNS rebinding protection enabled. This could enable the attacker to send unauthorized requests to the local MCP server, potentially invoking tools or accessing resources exposed by the server on behalf of the user, leading to unauthorized actions or data exposure.
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, upgrade the MCP TypeScript SDK to version 1.24.0 or later where DNS rebinding protection is enabled by default. Additionally, avoid running HTTP-based MCP servers locally without authentication, and ensure that enableDnsRebindingProtection is enabled if using StreamableHTTPServerTransport or SSEServerTransport.