Some Facebook users have found that the company stored message and call logs.
The company said it had permission to collection the information.
It looks like it's due to an old version of the Android mobile operating system being unclear about what data was being handed over.
This privacy scandal comes as Facebook is trying to rebuild trust after the Cambridge Analytica story.
Facebook has yet another privacy scandal on its hands, its second in two weeks.
This time, the company is being criticised for storing logs of message and calls of some of its users who signed into Facebook using its Android apps.
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Several Facebook users who requested an archive of their personal data following the recent Cambridge Analytica scandal found something concerning in their files: Facebook had stored months' worth of data about who they had been text messaging and calling.
To be clear: Facebook didn't have the text messages or recordings of phone calls. But it stored records of who some people texted, and when, as well as which phone numbers they called, when, and for how long.
Facebook rushed to try to stop the story getting out of control. It published a "fact check" on its blog in which it denied that it had done anything without users' permission.
It looks like the party at fault here isn't Facebook directly, but instead the Android operating system. Ars Technica points out that older versions of Android allowed apps to gain access to call and message logs when users actually just gave permission to read contacts.
It seems that all Facebook knew was that its users had given permission to share call and text logs with it. But users may never have explicitly chosen to do that.
Most people aren't going to research the story enough to learn about deprecated Android versions and app permissions, though. Instead, they're just going to see this as yet another Facebook privacy scandal.
Headlines matter for Facebook right now
Macquarie Research analysts said in a note published after the Cambridge Analytica scandal that "headlines matter" for Facebook.
"In this case, headlines matter very much for the stock," the analysts said in a note published on March 19. "While there will be plenty of journalists and others who can parse exactly what happened regarding this most recent issue involving Cambridge Analytica in terms of number of accounts and whether this was a 'data breach' or not, the details matter very little when looking at this through the narrow lens of an equity analyst. What matters for this stock, at this time, are the headlines."
Even if someone doesn't closely follow technology news, they'll have been aware of the Cambridge Analytica scandal, and now Facebook has another set of negative headlines such as "Facebook scraped call, text message data for years from Android phones." It's not a good look.
The timing of this Android story is particularly painful for Facebook. It comes as the company is trying to restore public trust following the Cambridge Analytica scandal. CEO Mark Zuckerberg even wrote a message to users and paid for it to be published in full-page newspaper ads in the US and UK.
Facebook's skeletons are tumbling out of the closet
Kevork Djansezian/Getty ImagesThe timing of the two stories gives the impression that Facebook is currently dealing with a privacy scandal. It is — but the issues aren't new. Instead, they're historic problems that the company didn't properly deal with at the time.
Facebook knew about the Cambridge Analytica scandal in 2015, when a Guardian journalist revealed that the research firm had harvested data on millions of Facebook users. Facebook had already changed its app settings to stop people handing over their friends' data, but it didn't ban Cambridge Analytica and continued to allow the company to operate on its platform.
And the new Android issue was due to a version of the Android operating system that allowed Facebook to gain message and call logs between 2015 and 2017. Again, it's an old issue for Facebook that isn't ongoing, but a lack of transparency and decisive action at the time has come back to hurt the firm.