diff --git a/boot/zephyr/serial_adapter.c b/boot/zephyr/serial_adapter.c
index 7ba4adb..f6f5162 100644
--- a/boot/zephyr/serial_adapter.c
+++ b/boot/zephyr/serial_adapter.c
@@ -148,6 +148,7 @@
 			cmd->len = cur;
 			sys_slist_append(lines_queue, &cmd->node);
 			cur = 0;
+			cmd = NULL;
 		}
 	}
 }