HBO, one of the biggest television networks in the world, got hacked on Monday morning. This is generally a bad thing as HBO is home to some of the biggest shows on TV ("Game of Thrones" being just one of them), and compromised copyrighted material could at least spell trouble for the company's integrity. At first, the network downplayed the hack, saying that not much was stolen and suggesting that the hack was not a critical breach of security. But, as a security contractor hired by the company found out, this is not the case.

HBO hack is more serious than initially assumed

The company that HBO hired is called IP Echelon, and these two have worked together before, mostly to erase links of infringed content from search engines like Google, according to DMCA takedown policies. This time, aside from the takedown, IP Echelon also got a chance to assess the damage that the hackers caused.

According to report by Variety, the security contractor learned that "the hackers did away with 'masses of copyrighted items' including documents, images, videos and sound."

When the hackers announced that they had access to confidential HBO data, they also released links to episodes of never-before-released episodes of shows like "Room 104," "Insecure," and "Ballers." They also released two episodes of "Barry," an upcoming comedy starring "Saturday Night Live" star Bill Hader.

"Barry" was not supposed to be released before 2018.

The hackers also leaked the script for an upcoming "Game of Thrones" episode.

1.5 terabytes of data stolen, including the personal information of an HBO executive

Perhaps the biggest and most controversial leak of all is the personal details of an HBO executive. The hackers released this data in the form of a text document which contained said executive's personal information.

Aside from having access to this executive's work email, they also released access details to various online portals -- including their personal health service provider, online newspaper subscriptions, and even their online banking accounts.

Since news of the hack broke, the perpetrators announced that they breached critical parts of HBO's network infrastructure.

This was corroborated by screenshots they released that showed that they indeed had access to administrator tools within HBO's systems. They also claimed that they obtained over 1.5 terabytes of data from the hack, which they promised to release in the near future.