diff --git a/Lib/test/test_marshal.py b/Lib/test/test_marshal.py
index 943aa55..0dd59d1 100644
--- a/Lib/test/test_marshal.py
+++ b/Lib/test/test_marshal.py
@@ -262,6 +262,11 @@
         testString = 'abc' * size
         marshal.dumps(testString)
 
+    def test_invalid_longs(self):
+        # Issue #7019: marshal.loads shouldn't produce unnormalized PyLongs
+        invalid_string = 'l\x02\x00\x00\x00\x00\x00\x00\x00'
+        self.assertRaises(ValueError, marshal.loads, invalid_string)
+
 
 def test_main():
     test_support.run_unittest(IntTestCase,
diff --git a/Misc/NEWS b/Misc/NEWS
index 90b59a7..ab14d9d 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,6 +12,9 @@
 Core and Builtins
 -----------------
 
+- Issue #7019: Raise ValueError when unmarshalling bad long data, instead
+  of producing internally inconsistent Python longs.
+
 Library
 -------
 
diff --git a/Python/marshal.c b/Python/marshal.c
index 52d2257..a4c831f 100644
--- a/Python/marshal.c
+++ b/Python/marshal.c
@@ -589,7 +589,8 @@
 			ob->ob_size = n;
 			for (i = 0; i < size; i++) {
 				int digit = r_short(p);
-				if (digit < 0) {
+				if (digit < 0 ||
+				    (digit == 0 && i == size-1)) {
 					Py_DECREF(ob);
 					PyErr_SetString(PyExc_ValueError,
 							"bad marshal data");