Millions of Facebook users have accidentally made their private posts completely public

Facebook is warning users to check their recent posts and photo uploads after discovering a bug in its composer that set the default privacy option to 'public'. 

Usually it's safe to assume that Facebook will use your preferred privacy settings, but unless you're in the habit of checking every time, you may have inadvertently revealed far more than you intended.

The bug affected posts published between May 18 and 27. Facebook is keen to point out that no privacy settings were changed retroactively, so nothing posted before then will have been exposed to the world without you realizing.

Accidental exposure

Facebook has now fixed the bug, and changed any posts made during that period to your usual privacy settings (though that could be a case of shutting the gate after the horse has bolted, depending on how much fun you had in those 10 days).

If there's a chance you might have been affected, you'll see a warning next time you log into Facebook, with an apology and list of posts you made during that period. Hopefully nothing you wouldn't want your boss, parents or partner to see.

In a statement to TechCrunch, the company said it's well aware that it needs to be more transparent about its privacy settings, and it'll publish more of these alerts when things go pear-shaped. Hopefully that won't be too often.

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Via Ars Technica