A Egyptian Hacker "Dr.FarFar" Claims To Have Hacked Mark Zuckerberg’s Facebook Profile and removed the Cover Photo as shown below in a screenshot:-


To achieve this he used a private exploit. According to post on the The Hacker News  he used the Report abuse option on Zuckerberg’s Cover image, and choose, ‘I don’t like this photo of me’ and edited the URL request using "Fiddler2 Debugger" Program.

It could be possible that Mark removed his Cover Photo himself, and someone is trying to take responsibility for the changes.

Here is the you-tube demonstration video by Dr.FarFar:-

 
When it comes to the Facebook hacking, Mark Zuckerberg have became a famous target for the security researchers/hackers. Its all due to the fame gets for mocking the famous "zuck" with his easy to remember  id "4" with high privacy features enabled. I will update this if any official news encounters.         

After the Forbes website and twitter hack, Syrian Electronic Army leaked account details of over 1 Million Forbes readers. The leaked detail contains login info of users such as email id and password. The password exposed are encrypted but can be cracked by simply using hash cracking tools or also some online sites.
 All the leak was uploaded to a secure server with two versions of the dump, a text file and other was compressed version of the text file. They posted URL of the dump in a tweet.



 Referring to their other tweet it looks they managed to do a successful phishing/social engineering attack on staff writer Alex Knapp and grabbed some important login credentials, which furthermore lead to the massive Forbes user database leak.
The leaked user details look like this (data has been deliberately altered):




To recover the passwords from this exposed database you'll need a lot of computing power and also time.
Still as there are millions of email id's included in the leak can be targeted for spamming, SEO and even phishing/Social engineering attacks.

Forbes later responded to this breach in their facebook post:-
  Security message: Forbes.com was targeted in a digital attack and our publishing platform was compromised. Users' email addresses may have been exposed. The passwords were encrypted, but as a precaution, we strongly encourage Forbes readers and contributors to change their passwords on our system, and encourage them to change them on other websites if they use the same password elsewhere. We have notified law enforcement. We take this matter very seriously and apologize to the members of our community for this breach.

This breach makes a plus one to the list of victims suffered from 'SEA' hack. The Syrian Electronic Army previously has targeted big organizations such as Microsoft, CNN, Paypal, Ebay, Facebook.