diff --git a/MdeModulePkg/Universal/Network/Ip4Dxe/Ip4Impl.c b/MdeModulePkg/Universal/Network/Ip4Dxe/Ip4Impl.c
index b5cd7b7d39..5a9d828703 100644
--- a/MdeModulePkg/Universal/Network/Ip4Dxe/Ip4Impl.c
+++ b/MdeModulePkg/Universal/Network/Ip4Dxe/Ip4Impl.c
@@ -1048,8 +1048,11 @@ Ip4Groups (
   // is decreamented each time an address is removed..
   //
   for (Index = IpInstance->GroupCount; Index > 0 ; Index--) {
-    Group = IpInstance->Groups[Index - 1];
-
+    Group = 0;  	
+    if(IpInstance->Groups != NULL) {
+  	  Group = IpInstance->Groups[Index - 1];
+  	}
+  	
     if ((GroupAddress == NULL) || EFI_IP4_EQUAL (&Group, GroupAddress)) {
       if (EFI_ERROR (Ip4LeaveGroup (IpInstance, NTOHL (Group)))) {
         return EFI_DEVICE_ERROR;
diff --git a/NetworkPkg/HttpBootDxe/HttpBootConfig.c b/NetworkPkg/HttpBootDxe/HttpBootConfig.c
index f32bf18e9d..81fceb2fd6 100644
--- a/NetworkPkg/HttpBootDxe/HttpBootConfig.c
+++ b/NetworkPkg/HttpBootDxe/HttpBootConfig.c
@@ -473,6 +473,9 @@ HttpBootFormCallback (
     // Get user input URI string
     //
     Uri = HiiGetString (CallbackInfo->RegisteredHandle, Value->string, NULL);
+    if(Uri == NULL) {
+    	return EFI_INVALID_PARAMETER;
+    }        
 
     //
     // The URI should be either an empty string (for corporate environment) ,or http(s) for home environment.
diff --git a/NetworkPkg/IpSecDxe/Ikev2/Utility.c b/NetworkPkg/IpSecDxe/Ikev2/Utility.c
index 2ca7f3c63c..8589af0b2a 100644
--- a/NetworkPkg/IpSecDxe/Ikev2/Utility.c
+++ b/NetworkPkg/IpSecDxe/Ikev2/Utility.c
@@ -2438,7 +2438,7 @@ Ikev2ChildSaParseSaPayload (
   IntegrityAlgorithm       = 0;
   EncryptAlgorithm         = 0;
   EncryptKeylength         = 0;
-  IsMatch                  = TRUE;
+  IsMatch                  = FALSE;
   IsSupportEsn             = FALSE;
   PreferIsSupportEsn       = FALSE;