Such objects are defined as oleObject elements in the XML:
<w:object w:dxaOrig="3795" w:dyaOrig="3555">
<v:shape id="_x0000_i1026" type="#_x0000_t75" style="width:32.85pt;height:30.55pt" o:ole="" fillcolor="window">
<v:imagedata r:id="rId9" o:title=""/>
</v:shape>
<o:OLEObject Type="Embed" ProgID="PBrush" ShapeID="_x0000_i1026" DrawAspect="Content" ObjectID="_1647182330" r:id="rId10"/>
</w:object>
Currently, they are skipped on import.