diff --git a/rmw_fastrtps_cpp/src/rmw_node.cpp b/rmw_fastrtps_cpp/src/rmw_node.cpp
index 3a39fc04d..a4915afa0 100644
--- a/rmw_fastrtps_cpp/src/rmw_node.cpp
+++ b/rmw_fastrtps_cpp/src/rmw_node.cpp
@@ -196,7 +196,8 @@ get_security_file_paths(
   std::string file_prefix("file://");
 
   for (size_t i = 0; i < num_files; i++) {
-    char * file_path = rcutils_join_path(node_secure_root, file_names[i]);
+    rcutils_allocator_t allocator = rcutils_get_default_allocator();
+    char * file_path = rcutils_join_path(node_secure_root, file_names[i], allocator);
 
     if (!file_path) {
       return false;
@@ -205,11 +206,11 @@ get_security_file_paths(
     if (rcutils_is_readable(file_path)) {
       security_files_paths[i] = file_prefix + std::string(file_path);
     } else {
-      free(file_path);
+      allocator.deallocate(file_path, allocator.state);
       return false;
     }
 
-    free(file_path);
+    allocator.deallocate(file_path, allocator.state);
   }
 
   return true;