hybris WCMS renderer pass attributes

I'm implementing a couple of CMS components via addOn extension and later add them to the storefront. I'm using a renderer instead of controller and I'm able to pass the attributes of my item to the jsp file. However, I have a problem, which might be pretty simple but I'm stuck. Let's say I want to pass the current user Id via the renderer to my JSP. Is this possible?

  protected Map<String, Object> getVariablesToExpose(final PageContext pageContext, final C component)
{
    final Map<String, Object> variables = new HashMap<String, Object>();
    for (final String property : cmsComponentService.getEditorProperties(component))
    {
        try
        {
            final Object value = modelService.getAttributeValue(component, property);
            variables.put(property, value);

        }
        catch (final AttributeNotSupportedException ignore)
        {
            // ignore
        }
    }
    return variables;
}

This is my code to get the properties of my item type and their values. But I don't want to have additional field called user id in my CMS component.