HBO's Twitter accounts hacked in latest cyberattack

Premium cable channel HBO has fallen victim yet again to a hacker attack. This time its official Twitter account was broken into, along with accounts for several of its most popular shows.

A group calling itself OurMine gained control of HBO’s main account Wednesday night, according to the Hollywood Reporter. It left a message in a tweet saying, "Hi, OurMine are here, we are just testing your security, HBO team please contact us to upgrade the security - ourmine .org -> Contact."

A second tweet read, "let's make #HBOHacked trending!"

The group also posted messages on the accounts for the shows "Vinyl," "true Blood," "Silicon Valley," "Looking," "Last Week Tonight," "Veep" and "The Leftovers."

A spokesperson for the channel told the Hollywood Reporter, “We are investigating.”

HBO was initially hacked several weeks ago, resulting in scripts, unaired episodes and other digital files from the channel's servers being released onto the internet.

Earlier this month, hackers using the name Mr. Smith posted a fresh cache of stolen HBO files online, and demanded that HBO pay a ransom of several million dollars in bitcoin to prevent further such releases.

The data dump included what appeared to be scripts from five "Game of Thrones" episodes and a month's worth of email from the account of Leslie Cohen, HBO's vice president for film programming. There were also internal documents, including a report of legal claims against the network and job offer letters to top executives.

The leak was a half-gigabyte sample of the 1.5 terabytes of data the hackers have claimed to steal, Wired reported. All of the leaked "Game of Thrones" scripts include a watermark with the hackers’ motto, “HBO is falling.” The data dump also included internal documents like emails, financial balance sheets, employment agreements and marketing strategy.

HBO, which previously acknowledged the theft of "proprietary information," said it's continuing to investigate and is working with police and cybersecurity experts. The network said at the time that it still doesn't believe that its email system as a whole has been compromised.

So far the HBO leaks have been limited, falling well short of the chaos inflicted on Sony in 2014. In that attack, hackers unearthed thousands of embarrassing emails and released personal information -- including salaries and Social Security numbers -- of nearly 50,000 current and former Sony employees.

Those behind the HBO hack claim to have more data, including scripts, upcoming episodes of HBO shows and movies, and information damaging to HBO.

It was not immediately clear if Wednesday's Twitter attack was related to the previous hacker attacks.

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