CVE-2026: Anthropic MCP SDK Remote Code Execution
A systemic 'by design' vulnerability in Anthropic's Model Context Protocol (MCP) SDK enables arbitrary remote code execution across all supported language implementations via unsafe STDIO transport defaults, affecting over 7,000 publicly accessible servers and 150 million downloads. The flaw has been independently confirmed across 10+ popular AI frameworks including LiteLLM, LangChain, and Flowise, with Anthropic declining to modify the protocol's architecture. This represents a significant AI supply chain risk with cascading exposure to sensitive data, API keys, and internal systems.