diff --git a/.gitmodules b/.gitmodules
index 7a76cbaf78d9..c1bed70a86c7 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -15,4 +15,4 @@
 	url = https://github.com/dmlc/dlpack
 [submodule "cub"]
 	path = cub
-	url = https://github.com/dmlc/cub
+	url = https://github.com/dmlc/cub.git