I'm a software engineer at Facebook working on security and privacy. This is simply a hoax. The html source shown in the video clearly says "No test user was deleted". We've verified in our logs that the victim account was manually deactivated by visiting https://www.facebook.com/deactivate.php. Anyone can visit https://www.facebook.com/whitehat/accounts/ and verify that the query parameter used by this endpoint is selected_test_users not selected_users. We've also audited our code to verify that there's no variant of this exploit that works against that endpoint or any other that we've found. In fact, the most recent code change to this endpoint was in April and was routine maintenance that had no security implications.
Re: #2. Basically correct. Reporting a range that includes all requests, including those that can't be disclosed individually, is the best outcome we've been able to negotiate so far. Here's the answer in the FAQ:
Why did you report the numbers for the United States in ranges?
We have reported the numbers for all criminal and national security requests to the maximum extent permitted by law. We continue to push the United States government to allow more transparency regarding these requests, including specific numbers and types of national security-related requests. We will publish updated information for the United States as soon as we obtain legal authorization to do so.
I'm a software engineer at Facebook. Requiring login for this page was a simple oversight and should be fixed sometime this evening California time. Sorry for the confusion.
I work on this at Facebook and we do permanently delete your content when you delete your account. It's an interesting distributed systems problem, and we're happy with the framework we've developed for this. We're working on a blog post with more details and hope to publish that soon.
When the delete button affects a single row in a single database table, it's indeed really simple. Even if it's a few rows on a single database, you can use transactions. Either way, the deletion succeeds or you surface an error message.
But for a large social site, it starts to become a more interesting distributed systems problem.
Even for a simple story with 4 likes, 12 comments, and likes on several of the comments, the data is sharded across several databases. Simple transactions no longer work. One option is looking for scalable distributed transactions. A more likely option is making sure deletions can be interrupted and restarted without losing state.
Now imagine a public figure whose post has tens of thousands of comments and hundreds of thousands likes. You may not be able to load all of those rows in a single request let alone delete them synchronously. Instead, you have to be able to process the deletion incrementally, reading and deleting some of the data then later picking up where you left off the last time you were interrupted.
Interestingly, the order of these operations can also be important. If you're interrupted between deleting a comment and deleting the likes on that comment, will you still be able to find the likes when you restart?
We've put a lot of work into a deletion framework that deals with these and many other issues. We're hoping to share more details about it in the future.
I'd like to think we wouldn't need to make such a fundamental change again in the future, but if we did decide it was necessary, I hope that we would give everyone plenty of time to make whatever change to their account was necessary to avoid painful outcomes like that.
My name is Scott Renfro, and I’m a software engineer at Facebook working on security and privacy. I thought I'd post the comment I submitted on the original blog post here as well. We’ve put a lot of work into making deletions permanent, so I can imagine how frustrated you must be. I’m pretty sure those story deletions are permanent, and I can’t think of any place where we can or do automatically restore user-deleted content months later.
If you happen to have any more details about specific stories that reappeared, I’d love to try and figure out exactly what happened. Admittedly, that may be difficult now that several months have passed.
As one of the other commenters mentioned, your Activity Log is a better place to get a full list of your activity and delete it item-by-item. It also shows posts that Timeline omits and includes other types of content such as likes and comments. This help page may be useful https://www.facebook.com/help/activitylog and you can find your Activity Log at https://www.facebook.com/me/allactivity?privacy_source=activ...
I couldn’t tell from your description, but one possibility is that you only saw and deleted the stories rendered on your Timeline, which is just a summary of your activity.
