Amazon is unwittingly acting as the retail channel for thousands of Android devices preloaded with nightmare advertising malware and with operating systems rooted, users and security boffins allege.
Other complaints relate to poor quality of manufacture.
Tens of thousands of the devices loaded with the Cloudsota malware are likely in circulation.
Chinese security firm Cheetah Mobile says it knows of 17,233 that had its antivirus installed; the number without their AV is feasibly much higher.
That trojan is a persistent advertising menace that resides within the Android KitKat boot image making it difficult to remove.
It can install ad applications so they cannot be removed, can uninstall security software and other apps, and will re-install itself if removed.
"We have notified companies involved whose products are found with pre-installed trojans … but unfortunately none have responded yet," company security boffins say noting that most affected devices sport the Allwinner chip.
"We assume that the unbranded tablet manufacturers do not pay any attention to user feedback, nor do they have the capability to offer a solution to this problem.
"When users boot the device, Cloudsota will visit the trojan creator’s server about every 30 minutes in order to obtain operating commands."
The scumware will change homepages and pull down applications from the command and control server before silently installing them.
Security boffins are confident attackers are located in China.
The advertising adware would certainly add extra profits for those players the sales chain who are in on the gambit.
The price of the tablet to this reporter does not seem low enough to warrant the need to recuperate cash by spraying ads to users, however. ®