Well I can't speak to backdoors in lenovos I did just recently purchase on eBay a replacement battery for my Sony VAIO... Auction page had "made in USA" plastered all over it, description was written in broken engrish. Upon receiving the battery I discovered it did not work, I contacted the seller with a return request and got an email back in even worse broken engrish from a "Mary Smith" with a link to a URL (hosted within china) to a driver installer and instructions for "instarration". I was to intarr the exe with the laptop plugged in to power and ethernet, reboot and leave power and Ethernet on "overnight" to fully charge the battery.
Backdoor attack campaign with Chinese origin? Gosh.. I dunno... what do YOU think?