diff --git a/platform/script-debugger/debugger-ui/src/RemoteVmConnection.kt b/platform/script-debugger/debugger-ui/src/RemoteVmConnection.kt
index 9228d5169d1f..9064c576b0be 100644
--- a/platform/script-debugger/debugger-ui/src/RemoteVmConnection.kt
+++ b/platform/script-debugger/debugger-ui/src/RemoteVmConnection.kt
@@ -45,6 +45,12 @@ abstract class RemoteVmConnection : VmConnection<Vm>() {
   
   @JvmOverloads
   fun open(address: InetSocketAddress, stopCondition: Condition<Void>? = null): Promise<Vm> {
+    if (address.isUnresolved) {
+      val error = "Host ${address.hostString} is unresolved"
+      setState(ConnectionStatus.CONNECTION_FAILED, error)
+      return rejectedPromise(error)
+    }
+
     this.address = address
     @Suppress("DEPRECATION")
     port = address.port
diff --git a/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XDebugSessionImpl.java b/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XDebugSessionImpl.java
index fbe57be0afcc..affa659cc3ed 100644
--- a/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XDebugSessionImpl.java
+++ b/platform/xdebugger-impl/src/com/intellij/xdebugger/impl/XDebugSessionImpl.java
@@ -916,8 +916,8 @@ public class XDebugSessionImpl implements XDebugSession {
 
   @Override
   public void stop() {
-    ProcessHandler processHandler = myDebugProcess.getProcessHandler();
-    if (processHandler.isProcessTerminated() || processHandler.isProcessTerminating()) return;
+    ProcessHandler processHandler = myDebugProcess == null ? null : myDebugProcess.getProcessHandler();
+    if (processHandler == null || processHandler.isProcessTerminated() || processHandler.isProcessTerminating()) return;
 
     if (processHandler.detachIsDefault()) {
       processHandler.detachProcess();