diff --git a/frontend/inventory/devices.component.html b/frontend/inventory/devices.component.html
index 2d41822..08f872c 100644
--- a/frontend/inventory/devices.component.html
+++ b/frontend/inventory/devices.component.html
@@ -60,6 +60,16 @@
   <hr/>
 </div>
 
+<div *ngIf="hostcheck" class="user-dialogue">
+    <div *ngIf="hostcheck.msg">{{hostcheck.msg}}</div>
+    <div>The authenticity of the host <span class="keyword">{{hostcheck.hostname}}</span> cannot be established.<br/>
+    <span class="keyword">{{hostcheck.keytype}}</span> key fingerprint is <span class="keyword">{{hostcheck.hexa}}</span>.</div>
+    <div>Are you sure you want to continue connecting?
+        <button (click)="hostcheckAnswer(true)">yes</button> /
+        <button (click)="hostcheckAnswer(false)">no</button>
+    </div>
+</div>
+
 <p class="msg-failure msg-rounded" *ngIf="err_msg"><span class="msg-close" (click)="err_msg=''">x</span>{{err_msg}}</p>
 <table class="items">
   <tr class="item_header">
diff --git a/frontend/inventory/devices.component.ts b/frontend/inventory/devices.component.ts
index b55650e..bbd43c5 100644
--- a/frontend/inventory/devices.component.ts
+++ b/frontend/inventory/devices.component.ts
@@ -8,6 +8,15 @@
 import {DevicesService} from './devices.service'
 import {SessionsService} from '../config/sessions.service'
 
+import {SocketService} from 'app/services/socket.service';
+
+enum ssh_hostcheck_status {
+    SSH_SERVER_KNOWN_CHANGED = 2,
+    SSH_SERVER_FOUND_OTHER = 3,
+    SSH_SERVER_FILE_NOT_FOUND = 4,
+    SSH_SERVER_NOT_KNOWN = 0
+}
+
 @Component({
     selector: 'inventoryDevices',
     templateUrl: './devices.component.html',
@@ -24,10 +33,12 @@
     namePlaceholder: string = "";
     id: number;
     err_msg = "";
+    hostcheck = null;
 
     constructor(
         private devicesService: DevicesService,
         private sessionsService: SessionsService,
+        public socketService: SocketService,
         private router: Router) {}
 
     getDevices(): void {
@@ -109,15 +120,32 @@
         }
     }
 
+    hostcheckAnswer(result: boolean) {
+        this.socketService.send('hostcheck_result', {'id': this.hostcheck.id, 'result': result});
+        delete this.hostcheck;
+    }
+
     connect(device: Device) {
         /* for backward compatibility */
         if (!device.name) {
             device.name = device.hostname + ":" + device.port;
         }
+        this.socketService.listen('hostcheck').subscribe((message: any) => {
+            this.hostcheck = message;
+            switch(message['state']) {
+            case ssh_hostcheck_status.SSH_SERVER_KNOWN_CHANGED:
+                this.hostcheck['msg'] = "Server has changed.";
+                break;
+            case ssh_hostcheck_status.SSH_SERVER_NOT_KNOWN:
+                this.hostcheck['msg'] = "Server not known.";
+                break;
+            }
+        });
         this.sessionsService.connect(device).subscribe(result => {
             if (result['success']) {
                 this.router.navigateByUrl('/netopeer/config');
             } else {
+                delete this.hostcheck;
                 this.err_msg = result['error-msg']
             }
         });
diff --git a/frontend/package.json b/frontend/package.json
index a31cf94..e651b9f 100644
--- a/frontend/package.json
+++ b/frontend/package.json
@@ -14,7 +14,7 @@
   },
   "homepage": "https://github.com/CESNET/Netopeer2GUI",
   "dependencies" : {
-    "@angular/material": "^5.0.0",
-    "@angular/cdk": "^5.0.0"
+    "@angular/material": "^6.0.0",
+    "@angular/cdk": "^6.0.0"
   }
 }