diff --git a/app/src/main/java/org/linphone/chat/ChatMessagesAdapter.java b/app/src/main/java/org/linphone/chat/ChatMessagesAdapter.java
index 1018d57d1..eeaba0b7a 100644
--- a/app/src/main/java/org/linphone/chat/ChatMessagesAdapter.java
+++ b/app/src/main/java/org/linphone/chat/ChatMessagesAdapter.java
@@ -364,7 +364,10 @@ public class ChatMessagesAdapter extends SelectableAdapter<ChatMessageViewHolder
             holder.eventLayout.setBackgroundResource(R.drawable.event_decoration_gray);
 
             Address address = event.getParticipantAddress();
-            String displayName = null;
+            if (address == null && event.getType() == EventLog.Type.ConferenceSecurityEvent) {
+                address = event.getSecurityEventFaultyDeviceAddress();
+            }
+            String displayName = "";
             if (address != null) {
                 LinphoneContact contact = ContactsManager.getInstance().findContactFromAddress(address);
                 if (contact != null) {
diff --git a/app/src/main/java/org/linphone/chat/ChatRoomViewHolder.java b/app/src/main/java/org/linphone/chat/ChatRoomViewHolder.java
index 5b65d19ae..75bd4aa70 100644
--- a/app/src/main/java/org/linphone/chat/ChatRoomViewHolder.java
+++ b/app/src/main/java/org/linphone/chat/ChatRoomViewHolder.java
@@ -162,10 +162,14 @@ public class ChatRoomViewHolder extends RecyclerView.ViewHolder implements View.
                     ContactAvatar.displayAvatar(contact, avatarLayout);
                 }
             } else {
-                Address remoteAddr;
+                Address remoteAddr = null;
                 if (mRoom.hasCapability(ChatRoomCapabilities.Encrypted.toInt())) {
                     Participant[] participants = mRoom.getParticipants();
-                    remoteAddr = participants[0].getAddress();
+                    if (participants.length > 0) {
+                        remoteAddr = participants[0].getAddress();
+                    } else {
+                        //TODO: error
+                    }
                 } else {
                     remoteAddr = mRoom.getPeerAddress();
                 }
diff --git a/app/src/main/res/drawable/event_decoration_red.xml b/app/src/main/res/drawable/event_decoration_red.xml
index 839e8ff17..45232fb87 100644
--- a/app/src/main/res/drawable/event_decoration_red.xml
+++ b/app/src/main/res/drawable/event_decoration_red.xml
@@ -2,6 +2,6 @@
 <shape
     xmlns:android="http://schemas.android.com/apk/res/android"
     android:shape="line">
-    <stroke android:width="50dp" android:color="@color/colorI"/>
-    <size android:height="1dp" />
+    <stroke android:width="1dp" android:color="@color/colorI"/>
+    <size android:height="1dp" android:width="50dp" />
 </shape>
\ No newline at end of file