When hackers broke into HBO's systems last month, the cable network's executives told staffers that they didn't believe its email system had been compromised "as a whole."
However, it does now look like at least some of the Time Warner-owned company's emails were compromised. According to a Monday Hollywood Reporter piece, the hackers have posted online not only a Game of Thrones script summary and marketing materials, but "a month's worth of emails" from an executive's inbox.
The hackers also sent the publication a video letter in which they demand an unreported sum of money, presumably to stop the release of more HBO documents. The leaked script summary explains Sunday's upcoming Game of Thrones episode, so fans should be on the alert for spoilers.
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Season 7 of Game of Thrones has brought in record numbers of viewers for HBO.
In a statement sent to The Hollywood Reporter and Variety, HBO said it anticipated the release of further leaks after the hacking incidents. It added that its forensic review had still not "given us a reason to believe that our email system as a whole has been compromised."
The hacking of U.S. entertainment companies has become something of a trend. 2014's Sony hack remains the most notorious incident, being attributed to North Korea, but hackers also recently targeted Netflix, leaking 10 episodes of Orange Is The New Black after the online video-streamer refused to pay up.