Ticket #19799: fix1.patch

django/contrib/auth/hashers.py

@@ -40 +40 @@
         hasher = get_hasher('unsalted_md5')
     else:
         algorithm = encoded.split('$', 1)[0]
+        if not algorithm:
+            return False
         hasher = get_hasher(algorithm)
 
     must_update = hasher.algorithm != preferred.algorithm