diff --git a/scripts/build.sh b/scripts/build.sh
index 45c83f0e..7f4ee1cf 100755
--- a/scripts/build.sh
+++ b/scripts/build.sh
@@ -227,7 +227,7 @@ EOF
         cd isolinux && \
         dd if=/dev/zero of=efiboot.img bs=1M count=10 && \
         sudo mkfs.vfat efiboot.img && \
-        LOOP_DEVICE=`losetup --find --show $PWD/efiboot.img` && \
+        LOOP_DEVICE=`sudo losetup --find --show $PWD/efiboot.img` && \
         mkdir efi && \
         sudo mount $LOOP_DEVICE efi && \
         sudo grub-install --efi-directory=efi --uefi-secure-boot --removable --no-nvram $LOOP_DEVICE && \