CVE-2026-47723 nebula-mesh: Web UI and API responses lack security headers (CSP, X-Frame-Options, HSTS, etc.)

nebula-mesh is a self-hosted control plane for Slack Nebula mesh virtual private network. Prior to version 0.3.1, none of the response paths in internal/web/ or internal/api/ set the standard browser-security headers. grep for Content-Security-Policy, X-Frame-Options, Strict-Transport-Security,...