netbox/netbox/templates/exceptions/permission_error.html

{% extends '500.html' %}

{% block message %}
  <p>
    A file permission error was detected while processing this request. Common causes include the following:
  </p>
  <p>
    <i class="mdi mdi-alert"></i> <strong>Insufficient write permission to the media root</strong> - The configured
    media root is <code>{{ settings.MEDIA_ROOT }}</code>. Ensure that the user NetBox runs as has access to write files
    to all locations within this path.
  </p>
{% endblock message %}