diff --git a/misc/build.func b/misc/build.func
index d0df26b3..e48e17b6 100644
--- a/misc/build.func
+++ b/misc/build.func
@@ -22,6 +22,7 @@ variables() {
   DIAGNOSTICS="yes"                                 # sets the DIAGNOSTICS variable to "yes", used for the API call.
   METHOD="default"                                  # sets the METHOD variable to "default", used for the API call.
   RANDOM_UUID="$(cat /proc/sys/kernel/random/uuid)" # generates a random UUID and sets it to the RANDOM_UUID variable.
+  CTTYPE="${CTTYPE:-${CT_TYPE:-1}}"
   #CT_TYPE=${var_unprivileged:-$CT_TYPE}
 }