void NavigatorImpl::DidStartMainFrameNavigation(
    const GURL& url,
    SiteInstanceImpl* site_instance,
    NavigationHandleImpl* navigation_handle) {
  NavigationEntryImpl* pending_entry = controller_->GetPendingEntry();
  bool has_browser_initiated_pending_entry =
      pending_entry && !pending_entry->is_renderer_initiated();

  bool has_transient_entry = !!controller_->GetTransientEntry();

  if (!has_browser_initiated_pending_entry && !has_transient_entry) {
    std::unique_ptr<NavigationEntryImpl> entry =
        NavigationEntryImpl::FromNavigationEntry(
            controller_->CreateNavigationEntry(
                url, content::Referrer(), ui::PAGE_TRANSITION_LINK,
                true /* is_renderer_initiated */, std::string(),
                controller_->GetBrowserContext()));
    entry->set_site_instance(site_instance);
    if (pending_entry) {
      entry->set_transferred_global_request_id(
          pending_entry->transferred_global_request_id());
      entry->set_should_replace_entry(pending_entry->should_replace_entry());
      entry->SetRedirectChain(pending_entry->GetRedirectChain());
    }

    if (navigation_handle)
      navigation_handle->update_entry_id_for_transfer(entry->GetUniqueID());

    controller_->SetPendingEntry(std::move(entry));
    if (delegate_)
      delegate_->NotifyChangedNavigationState(content::INVALIDATE_TYPE_URL);
  }
}

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.