diff --git a/Makefile b/Makefile
index 3e8c4eb..1058ffd 100644
--- a/Makefile
+++ b/Makefile
@@ -44,4 +44,4 @@ install-exclude:
 # target: install-systemd - Install systemd timer and service files
 install-systemd:
 	install -d $(DEST_SYSTEMD)
-	install $(SRCS_SYSTEMD) $(DEST_SYSTEMD)
+	install -m 0644 $(SRCS_SYSTEMD) $(DEST_SYSTEMD)