diff --git a/IntelFrameworkModulePkg/Bus/Isa/Ps2KeyboardDxe/Ps2KbdTextIn.c b/IntelFrameworkModulePkg/Bus/Isa/Ps2KeyboardDxe/Ps2KbdTextIn.c
index 637d054953..b1d4fa2fdb 100644
--- a/IntelFrameworkModulePkg/Bus/Isa/Ps2KeyboardDxe/Ps2KbdTextIn.c
+++ b/IntelFrameworkModulePkg/Bus/Isa/Ps2KeyboardDxe/Ps2KbdTextIn.c
@@ -684,7 +684,11 @@ KeyboardUnregisterKeyNotify (
   if (NotificationHandle == NULL) {
     return EFI_INVALID_PARAMETER;
   } 
-  
+
+  if (((KEYBOARD_CONSOLE_IN_EX_NOTIFY *) NotificationHandle)->Signature != KEYBOARD_CONSOLE_IN_EX_NOTIFY_SIGNATURE) {
+    return EFI_INVALID_PARAMETER;
+  } 
+   
   ConsoleInDev = TEXT_INPUT_EX_KEYBOARD_CONSOLE_IN_DEV_FROM_THIS (This);
   
   //
diff --git a/MdeModulePkg/Bus/Usb/UsbKbDxe/EfiKey.c b/MdeModulePkg/Bus/Usb/UsbKbDxe/EfiKey.c
index c78305e780..e2c86b07b4 100644
--- a/MdeModulePkg/Bus/Usb/UsbKbDxe/EfiKey.c
+++ b/MdeModulePkg/Bus/Usb/UsbKbDxe/EfiKey.c
@@ -1102,6 +1102,10 @@ USBKeyboardUnregisterKeyNotify (
   if (NotificationHandle == NULL) {
     return EFI_INVALID_PARAMETER;
   }  
+
+  if (((KEYBOARD_CONSOLE_IN_EX_NOTIFY *) NotificationHandle)->Signature != USB_KB_CONSOLE_IN_EX_NOTIFY_SIGNATURE) {
+    return EFI_INVALID_PARAMETER;
+  } 
   
   UsbKeyboardDevice = TEXT_INPUT_EX_USB_KB_DEV_FROM_THIS (This);
   
diff --git a/MdeModulePkg/Universal/Console/ConSplitterDxe/ConSplitter.c b/MdeModulePkg/Universal/Console/ConSplitterDxe/ConSplitter.c
index 78d9e9497f..7650ce4b6d 100644
--- a/MdeModulePkg/Universal/Console/ConSplitterDxe/ConSplitter.c
+++ b/MdeModulePkg/Universal/Console/ConSplitterDxe/ConSplitter.c
@@ -3921,6 +3921,10 @@ ConSplitterTextInUnregisterKeyNotify (
     return EFI_INVALID_PARAMETER;
   }
 
+  if (((TEXT_IN_EX_SPLITTER_NOTIFY *) NotificationHandle)->Signature != TEXT_IN_EX_SPLITTER_NOTIFY_SIGNATURE) {
+    return EFI_INVALID_PARAMETER;
+  } 
+  
   Private = TEXT_IN_EX_SPLITTER_PRIVATE_DATA_FROM_THIS (This);
 
   //
diff --git a/MdeModulePkg/Universal/Console/TerminalDxe/TerminalConIn.c b/MdeModulePkg/Universal/Console/TerminalDxe/TerminalConIn.c
index ae4ea818de..44b62d7aed 100644
--- a/MdeModulePkg/Universal/Console/TerminalDxe/TerminalConIn.c
+++ b/MdeModulePkg/Universal/Console/TerminalDxe/TerminalConIn.c
@@ -445,6 +445,10 @@ TerminalConInUnregisterKeyNotify (
     return EFI_INVALID_PARAMETER;
   }
 
+  if (((TERMINAL_CONSOLE_IN_EX_NOTIFY *) NotificationHandle)->Signature != TERMINAL_CONSOLE_IN_EX_NOTIFY_SIGNATURE) {
+    return EFI_INVALID_PARAMETER;
+  } 
+  
   TerminalDevice = TERMINAL_CON_IN_EX_DEV_FROM_THIS (This);
 
   NotifyList = &TerminalDevice->NotifyList;
diff --git a/Nt32Pkg/WinNtGopDxe/WinNtGopInput.c b/Nt32Pkg/WinNtGopDxe/WinNtGopInput.c
index be41a8e854..e9866740ce 100644
--- a/Nt32Pkg/WinNtGopDxe/WinNtGopInput.c
+++ b/Nt32Pkg/WinNtGopDxe/WinNtGopInput.c
@@ -797,7 +797,11 @@ WinNtGopSimpleTextInExUnregisterKeyNotify (
   if (NotificationHandle == NULL) {
     return EFI_INVALID_PARAMETER;
   } 
-  
+
+  if (((WIN_NT_GOP_SIMPLE_TEXTIN_EX_NOTIFY *) NotificationHandle)->Signature != WIN_NT_GOP_SIMPLE_TEXTIN_EX_NOTIFY_SIGNATURE) {
+    return EFI_INVALID_PARAMETER;
+  } 
+
   Private = GOP_PRIVATE_DATA_FROM_TEXT_IN_EX_THIS (This);
 
   for (Link = Private->NotifyList.ForwardLink; Link != &Private->NotifyList; Link = Link->ForwardLink) {