Insecure Default Initialization of Resource Affecting semgrep package, versions <1.145.0-r0


Severity

Recommended
0.0
high
0
10

Snyk's Security Team recommends NVD's CVSS assessment. Learn more

Threat Intelligence

EPSS
0.03% (9th percentile)

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  • Snyk IDSNYK-WOLFILATEST-SEMGREP-15414923
  • published5 Mar 2026
  • disclosed2 Dec 2025

Introduced: 2 Dec 2025

CVE-2025-66416  (opens in a new tab)
CWE-1188  (opens in a new tab)

How to fix?

Upgrade Wolfi semgrep to version 1.145.0-r0 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream semgrep package and not the semgrep package as distributed by Wolfi. See How to fix? for Wolfi relevant fixed versions and status.

The MCP Python SDK, called mcp on PyPI, is a Python implementation of the Model Context Protocol (MCP). Prior to version 1.23.0, tThe Model Context Protocol (MCP) Python 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 using FastMCP with streamable HTTP or SSE transport, and has not configured TransportSecuritySettings, 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 1.23.0.

CVSS Base Scores

version 3.1