CVE-2025-66414

HIGH EPSS 35.6%
Published Dec 2, 20257mo ago · Modified Jun 17, 20262w ago
7.6 CVSS 4.0
High
Find Similar
Published Dec 2, 2025 7mo ago
Last Modified Jun 17, 2026 2w ago

Description

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 Details

Base Score
7.6
Exploitability
—
Impact
—
Vector string
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/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
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction P
Scope X

Threat Intelligence

EPSS Exploit Probability
35.6% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-1188

Affected Products 1

VendorProductVersionRange
lfprojectsmcp_typescript_sdk* <1.24.0

References 2

  • github.com https://github.com/modelcontextprotocol/typescript-sdk/commit/09623e2aa5044f9e9da62c73d820a8250b9d97ed
    Patch
  • github.com https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-w48q-cv73-mx4w
    Vendor Advisory

Remediation

  • github.com https://github.com/modelcontextprotocol/typescript-sdk/commit/09623e2aa5044f9e9da62c73d820a8250b9d97ed
    Patch