Response PageHandler::GetNavigationHistory(
    int* current_index,
    std::unique_ptr<NavigationEntries>* entries) {
  WebContentsImpl* web_contents = GetWebContents();
  if (!web_contents)
    return Response::InternalError();

  NavigationController& controller = web_contents->GetController();
  *current_index = controller.GetCurrentEntryIndex();
  *entries = NavigationEntries::create();
  for (int i = 0; i != controller.GetEntryCount(); ++i) {
    auto* entry = controller.GetEntryAtIndex(i);
    (*entries)->addItem(
        Page::NavigationEntry::Create()
            .SetId(entry->GetUniqueID())
            .SetUrl(entry->GetURL().spec())
            .SetUserTypedURL(entry->GetUserTypedURL().spec())
            .SetTitle(base::UTF16ToUTF8(entry->GetTitle()))
            .SetTransitionType(TransitionTypeName(entry->GetTransitionType()))
            .Build());
  }
  return Response::OK();
}

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.