A photo she posted to her Facebook account of her family, including the Facebook CEO, playing around with Facebook's new Poke app, ended up on Twitter.
The photo was tweeted by Callie Schweitzer, a marketing executive at Vox Media, when she thought that it was a public photo on Facebook. Schweitzer followed or subscribed to Zuckerberg's public Facebook feed and thought the update was public.
But it wasn't. According to Buzzfeed and Zuckerberg's tweets, Schweitzer was friends with another one of the Zuckerberg sisters and because she was tagged she was able to see it. ".@randizuckerberg demonstrates her family's response to Poke #GAH," Schweitzer tweeted along with the photo.
It didn't take long for Randi Zuckerberg to respond. "Not sure where you got this photo. I posted it to friends only on FB. You reposting it to Twitter is way uncool," she said on Twitter. Schweitzer clarified that she thought it was public, apologized and removed the photo promptly. Of course, this is the Internet - the photo wasn't removed entirely. Many web sites, including Buzzfeed, Business Insider, Mashable and Gizmodo all ran the photo. VentureBeat even said even Zuckerbergs are tripped up by Facebook's privacy settings.
However, Zuckerberg tweeted that "it's not about privacy settings, it's about human decency."
The snafu does illustrate something Facebook has started highlighting in its recent privacy controls overhaul - that your Timeline is separate than other places on Facebook and that tagged photos can still be viewed by others. Starting last Friday, Facebook rolled out its redesigned and cleaner privacy tools. One of the additions included educational messages, which pop up when you untag a photo. The message tells users that the photo still might be visible by others.
AllThingD's Mike Issac argues though that this has nothing to do with Facebook privacy settings, but rather bad judgement. "No matter how many privacy settings you tweak, no matter what you consider proper 'digital etiquette,' there is no accounting for the taste and discretion of your friends," Issac wrote.
In Zuckerberg's case, it's hard to say where the blame should be put, but unfortunately for her, the photo is now visible to many, many others.