Speaking at a press conference, Joon Kim, the acting U.S. attorney for the Southern District of NY, called Mesri "an experienced and sophisticated hacker who has been wreaking havoc on computer systems around the world for some time".
But Mesri is now in Iran, and United States officials have accepted that it would be hard to detain him.
US prosecutors say a member of an Iran-based hacking group tried to extort HBO out of $6 million in digital currency by stealing unaired episodes and scripts of hit shows like "Game of Thrones".
An important element in the case was the supposed connection between Mesri and the Iranian government, a line being pushed by the Justice Department.
A warrant has been issued for his arrest, and should he get caught, Mesri could face up a maximum sentence of 20 years in prison: "up to five years for each of the four charges related to computer fraud; a two-year mandatory sentence for aggravated identity theft; and up to two years in prison for the extortion charge".
Over the next couple months, Mr. Mesri compromised user accounts that belonged to HBO employees and used them repeatedly to gain unauthorized access and steal proprietary information from the company, the indictment said.More news: Dog Owners May Have Healthier Hearts, Study Finds
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When contacted by WorldPost, HBO spokesman Jeff Cusson declined to comment.
Although the document doesn't state that the Iranian Regime told Mesri to attack HBO, it should be made clear that he is deeply tied to the Regime and would be unlikely to attack such a prominent target without their permission. The hack at HBO happened nearly three years after a high-profile breach at Sony Corp., which unleashed a trove of emails that embarrassed top executives. Included was an image of "Game of Thrones" Night King character, leader of an army of zombies, with the words, "Good luck HBO".
He first demanded $5.5 million worth of Bitcoin (an untraceable cryptocurrency) in order to not release HBO's shows for torrenting, but when HBO refused he upped it to $6 million and threatened to destroy their data servers.
Rather than keep quiet, prosecutors say Mesri "undertook efforts to promote the leaks", actively seeking journalists to publicise the story.
"Unfortunately, I suspect that this will not be the last time we charge cyber offences against hackers with ties to the Iranian government", Kim said.