diff --git a/Misc/NEWS.d/next/Core and Builtins/2018-08-23-21-32-27.bpo-18560.5q_c1C.rst b/Misc/NEWS.d/next/Core and Builtins/2018-08-23-21-32-27.bpo-18560.5q_c1C.rst
new file mode 100644
index 0000000..4c1f060
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2018-08-23-21-32-27.bpo-18560.5q_c1C.rst
@@ -0,0 +1 @@
+Fix potential NULL pointer dereference in sum().
diff --git a/Python/bltinmodule.c b/Python/bltinmodule.c
index 21f6e66..4b819da 100644
--- a/Python/bltinmodule.c
+++ b/Python/bltinmodule.c
@@ -2363,6 +2363,11 @@
             }
             /* Either overflowed or is not an int. Restore real objects and process normally */
             result = PyInt_FromLong(i_result);
+            if (result == NULL) {
+                Py_DECREF(item);
+                Py_DECREF(iter);
+                return NULL;
+            }
             temp = PyNumber_Add(result, item);
             Py_DECREF(result);
             Py_DECREF(item);