GCVE-110-OSM-2026-5113

Exfiltrates system metadata (hostname, working directory, npm user agent, Node version, platform) to an attacker-controlled Cloudflare Workers endpoint via HTTPS POST in a postinstall hook. The package typosquats @modelcontextprotocol/server-sequential-thinking and was published simultaneously with six other fake mcp-server-* packages by the same publisher as a coordinated MCP namespace squatting campaign. **Trigger** (`postinstall`): executes `node index.js` at npm install time. **Collection**: reads `os.hostname()`, `process.cwd()`, `process.env.npm_config_user_agent`, `process.version`, `os.platform()`, `os.arch()`, `new Date().toISOString()`. No file system reads or credential access confirmed. **Exfiltration**: JSON-serializes all fields and POSTs to `https://npx-canary-log.vulnerable-live.workers.dev/log` via `https.request`. The endpoint URL is a literal constant confirmed in `index.js` source.