App.Actions.MAIL_ACC.disable_unlimited = function(elm, source_elm) {
    $(elm).data('checked', false);
    if ($(elm).data('prev_value') && $(elm).data('prev_value').trim() != '') {
        var prev_value = $(elm).data('prev_value').trim();
        $(elm).val(prev_value);
        if (App.Helpers.isUnlimitedValue(prev_value)) {
            $(elm).val('0');
        }
    }
    else {
        if (App.Helpers.isUnlimitedValue($(elm).val())) {
            $(elm).val('0');
        }
    }
    $(elm).attr('disabled', false);
    $(source_elm).css('opacity', '0.5');
}
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.