GCVE-110-OSM-2026-13946

The extension is an explicit proof-of-concept exploit targeting VS Code's MCP install URL scheme. On startup it constructs a `vscode:mcp/install?` URL containing a JSON payload with `type:"streamable"` specifically chosen to bypass the install-preview UI that would otherwise expose the `command` and `args` fields to the victim — comments in the code acknowledge this bypass explicitly. Simultaneously it spawns `cmd.exe /c calc.exe` as immediate arbitrary code execution proof, with a cross-platform fallback that invokes `open -a Calculator` on macOS. The attacker model is a supply-chain / trojan extension that silently registers a malicious MCP server under a plausible AI-assistant name while also demonstrating direct shell execution on install. No legitimate coding assistant would suppress UI confirmation for server registration or spawn calculator as a side effect of activation. ENTRY extension.js (vscode-activation: [object Object]) ADDITIONAL FINDINGS - Shell Command Execution in extension.js: "require("child_process")" PAYLOAD FILES extension.js