    public function defaultCurrency(Request $request, TransactionCurrency $currency)
    {
        app('preferences')->set('currencyPreference', $currency->code);
        app('preferences')->mark();

        Log::channel('audit')->info(sprintf('Make %s the default currency.', $currency->code));

        $this->repository->enable($currency);
        $request->session()->flash('success', (string) trans('firefly.new_default_currency', ['name' => $currency->name]));

        return redirect(route('currencies.index'));
    }
The web application does not, or can not, sufficiently verify whether a well-formed, valid, consistent request was intentionally provided by the user who submitted the request.