diff --git a/libsel4utils/src/vspace/bootstrap.c b/libsel4utils/src/vspace/bootstrap.c
index 336e234..385ce6b 100644
--- a/libsel4utils/src/vspace/bootstrap.c
+++ b/libsel4utils/src/vspace/bootstrap.c
@@ -310,6 +310,7 @@
     if (data->top_level == NULL) {
         return -1;
     }
+    memset(data->top_level, 0, sizeof(vspace_mid_level_t));
 
     common_init_post_bootstrap(new_vspace, map_page);