diff --git a/pkg/core/native/native_test/oracle_test.go b/pkg/core/native/native_test/oracle_test.go
index bc32eadde..dec7ab41d 100644
--- a/pkg/core/native/native_test/oracle_test.go
+++ b/pkg/core/native/native_test/oracle_test.go
@@ -156,7 +156,7 @@ func TestOracle_Request(t *testing.T) {
 		putOracleRequest(t, helperValidatorInvoker, "url", nil, "handleRecursive", []byte{}, gasForResponse)
 		tx := prepareResponseTx(t, 2)
 		e.AddNewBlock(t, tx)
-		//		e.CheckFault(t, tx.Hash(), "")
+		e.CheckFault(t, tx.Hash(), "Oracle.finish called from non-entry script")
 		aer, err := e.Chain.GetAppExecResults(tx.Hash(), trigger.Application)
 		require.NoError(t, err)
 		require.Equal(t, 2, len(aer[0].Events)) // OracleResponse + Invocation
diff --git a/pkg/core/native/oracle.go b/pkg/core/native/oracle.go
index 62ac80b00..330e640a7 100644
--- a/pkg/core/native/oracle.go
+++ b/pkg/core/native/oracle.go
@@ -276,6 +276,12 @@ func (o *Oracle) finish(ic *interop.Context, _ []stackitem.Item) stackitem.Item
 
 // FinishInternal processes an oracle response.
 func (o *Oracle) FinishInternal(ic *interop.Context) error {
+	if ic.VM.Istack().Len() != 2 {
+		return errors.New("Oracle.finish called from non-entry script")
+	}
+	if ic.Invocations[o.Hash] != 1 {
+		return errors.New("Oracle.finish called multiple times")
+	}
 	resp := getResponse(ic.Tx)
 	if resp == nil {
 		return ErrResponseNotFound