CVE-2025-66414
CVE-2025-66414 · DNS Rebinding Protection Disabled by Default in Model Context Protocol TypeScript SDK for Servers Running on Localhost
This page contains facts from public vulnerability sources. Check the original advisory before updating.
MCP TypeScript SDK is the official TypeScript SDK for Model Context Protocol servers and clients. Prior to 1.24.0, The Model Context Protocol (MCP) TypeScript SDK does not enable DNS rebinding protection by default for HTTP-based servers. When an HTTP-based MCP server is run on localhost without authentication with StreamableHTTPServerTransport or SSEServerTransport and has not enabled enableDnsRebindingProtection, a malicious website could exploit DNS rebinding to bypass same-origin policy restrictions and send requests to the local MCP server. This could allow an attacker to invoke tools or access resources exposed by the MCP server on behalf of the user in those limited circumstances. Note that running HTTP-based MCP servers locally without authentication is not recommended per MCP security best practices. This issue does not affect servers using stdio transport. This vulnerability is fixed in 1.24.0.
CVSS 7.6 · High · EPSS 0.5% · Fix available
- Published
- Updated
Stack: node
Affected products and versions
typescript-sdk
- Versions
- < 1.24.0: Affected
No fix published
@modelcontextprotocol/sdk npm
- Affected ranges
- SEMVER: < 1.24.0
Update to 1.24.0