diff --git a/src/logging.c b/src/logging.c
index 76e88d5..100f831 100644
--- a/src/logging.c
+++ b/src/logging.c
@@ -613,15 +613,14 @@ static void uc_log_file_rotate_size(struct UCLogDestination *dest)
     //rotate existing .num files
     i = dest->type.file.rotate.size_settings.num_files -1;
     while (i > 0) {
-        sprintf(new_filename, "%s.%d", dest->type.file.file_name, i);
-        sprintf(old_filename, "%s.%d", dest->type.file.file_name, i - 1);
+        snprintf(new_filename, sizeof new_filename, "%s.%d", dest->type.file.file_name, i);
+        snprintf(old_filename, sizeof old_filename, "%s.%d", dest->type.file.file_name, i - 1);
         rename(old_filename, new_filename);
         i--;
     }
 
-    sprintf(new_filename, "%s.0", dest->type.file.file_name);
-
     //rename current file
+    sprintf(new_filename, "%s.0", dest->type.file.file_name);
     rename(dest->type.file.file_name, new_filename);
 
     //re-open current file