diff --git a/core/vm/stack.go b/core/vm/stack.go
index b551de272..2be5c3dbe 100644
--- a/core/vm/stack.go
+++ b/core/vm/stack.go
@@ -15,7 +15,7 @@ type stack struct {
 }
 
 func (st *stack) Data() []*big.Int {
-	return st.data
+	return st.data[:st.ptr]
 }
 
 func (st *stack) push(d *big.Int) {