EBay is barring listings for a smartphone after reports the model is pre-installed with spyware in its Chinese factory.
A German security firm reported on Tuesday that the Android-powered Star N9500 sent personal data to a computer server in China, adding that the Trojan could not be removed.
It said the malware was disguised as the legitimate Google Play Store app.
The handset remains on sale on Amazon, which could not be reached for comment.
But eBay said it was rolling out the ban globally.
"Due to reports that some Star 9500 smartphones are loaded with spyware, eBay is not allowing the sale of these devices as a precautionary measure," a spokesman told the BBC.
Although the brand Star is far from being a household name, the handset may have appealed to some customers because of its close resemblance to the Samsung Galaxy S4 coupled with the fact it sells for about a third of the cost.
Security firm G Data said it was alerted to the case after receiving tip-offs from its customers.
"The spyware runs in the background and cannot be detected by users," it said.
"Unbeknownst to the user, the smartphone sends personal data to a server located in China and is able to covertly install additional applications.
"This makes it possible to retrieve personal data, intercept calls and online banking data, read emails and text messages or control the camera and microphone remotely.
"The program also blocks the installation of security updates."
The Associated Press news agency has reported that although several Shenzhen-based firms used eBay and other sites to sell the model, it had been unable to track down the manufacturer.
If the allegations are true, it is not known whether the manufacturer itself would have been aware of what was being done at its plant.
This is not the first time that a Chinese factory has been accused of shipping devices preinstalled with malware.
In 2012 Microsoft reported that several PC makers in the country had been found to load malicious programs onto their computers.
Then, last year German firm E-Plus reported that some of its China-made Android smartphones were being shipped with SD memory cards infected with a computer worm.