According to Entertainment Weekly, hackers have penetrated HBO's systems and posted forthcoming episodes of "Ballers" and "Room 104" online as well as a script for the as-yet-unaired episode four of "Game Of Thrones."
Hackers claimed to have stolen 1.5TB of data from the company and said that there was more material yet to come.
Representatives for HBO told EW that there was a "cyber incident" which resulted in the "compromise of proprietary information." "We immediately began investigating the incident and are working with law enforcement and outside cybersecurity firms," a network representative said to the magazine.
"Game of Thrones" is already among the the most pirated shows online, but the release of episodes before they air would represent a significant escalation. Earlier this year, ahead of that season's premiere on Netflix.
HBO did not immediately respond to CNET's request for a comment.