SAN FRANCISCO (KCBS) — It’s not a feature they’re advertising: tens of thousands of cheap smartphones are reportedly sending all user text messages to China every three days.

The secret backdoor software was recently discovered by security researchers. What’s not clear is whether this represents a way to mine data for advertisers—or an attempt by the Chinese government to collect intelligence.

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The Chinese company responsible for the software says its code runs on hundreds of millions of phones, car, and other devices. The software transmits the text messages, contact lists, call logs, and location information to a Chinese server.

The code comes pre-installed on Android phones and the surveillance is not disclosed to users, according to the report.

Here in the U.S., the code showed up on inexpensive smartphones sold by a company named BLU Products, which said it has updated the software to close that Chinese backdoor.

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A Palo Alto lawyer for the software firm, Shanghai Adups Technology Company said the software was installed to help a Chinese phone manufacturer monitor user behavior and was not intended for American phones.

AdUps did fix the problem on 120,000 Blu phones, but that’s not the end of the story because that AdUps software is running on seven hundred million phones.

“We are not in a position where we can know which devices are affected or potentially affected. Google, every time someone has an Android operating system on their phone, they would go through an Android certification process. So, Google potentially knows the scope and all the devices that potentially use this firmware update provider,” Researcher Azzedine Benameur said.

But, Google refuses to turn over the list. A Google spokesperson said the company is working closely with Kryptowire, but it is not obligated to tell them which phones use AdUps.

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