Cursor MCP JSON Zero-Click Configuration RCE (CVE-2025-54136) - ATR-2026-00419 (69da10d0-d7de-53c4-b0ba-bbdcd8909168)
Detects exploitation of CVE-2025-54136 in Cursor and the same-class issue surfaced by the OX Security MCP-by-design batch (2026-04-15) across Windsurf, Claude Code, Gemini CLI, and GitHub Copilot. The IDE's MCP config file (.cursor/mcp.json or equivalent) is auto-loaded on workspace open and treats the command and args fields as OS exec targets. An attacker who can modify this file via supply chain (npm package post-install, malicious .vscode/.cursor commit, repo template) achieves zero-click RCE the moment a developer opens the project. No prompt, no consent dialog.