Email has replaced the phone as a means of casual conversation in Hollywood—people have the kind of casual "conversations" over email that they'd previously only had in person. And if they trusted the correspondent—the way Sony Pictures Co-Chairman Amy Pascal trusted producer Scott Rudin—they weren't worried about emails being forwarded.
But that's not the case anymore. Sony's hacking scandal has people in Hollywood taking a pause before sending emails that contain confidential info.
The security breach at Sony's movie studio revealed executive's salaries, unpublished scripts and aliases that actors use when traveling incognito.
The stolen info also exposed a series of comments Pascal made about President Barack Obama. Pascal apologized for what she called "insensitive and inappropriate" emails in a statement to Deadline.com.
Hollywood execs are treating emails more like formal letters now. People who have done business with Sony in the past are searching their email archives for anything that could potentially be leaked, sources told CNBC.
The question now is how bad can it really be and who will be hurt the most. "[T]here's going to be consequences for senior people at the studio," said Sharon Waxman, founder and editor in chief of TheWrap.
"The studio has to go on with its business and it's drip drip drip everyday of an unknown damage hitting the studio—and embarrassment, another piece of information," Waxman told CNBC's "Street Signs" on Thursday.
She questioned the studio's ability to withstand the scandal with its current leadership.
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The leaked emails revealed how Sony executives negotiate and how much they pay different people for different types of deals. Industry insiders say this could put the company at a massive disadvantage going forward, when it comes to negotiating in Hollywood.
So next time an agent or lawyer is negotiating a contract, they'll know if Sony's first offer is usually 50 percent less than where contracts land, or whether the studio has a track record of giving in.
Security specialists have called the attack extraordinary. Cybersecurity researchers who have analyzed the malicious software used in the attack say that technical indicators suggest North Korean hackers launched the assault, Reuters reported earlier this week.
FBI officials have not attributed the incident to North Korea at this point, but Sony hasn't ruled out that country or current employees as suspects, Waxman said, citing sources close the the matter.
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"It's possible that it was a combination of those two, but there doesn't seem to be a clear sense of who did it and why," Waxman said.
Entertainment and technology attorney Jonathan Handel said the hacks are a wake-up call for corporate America and "I hope also for the computer, which has really kind of failed us."
He said all computer keyboards should come equipped with a standard fingerprint reader. In addition, software-makers like Microsoft should begin to stress the importance of encrypting all PC files.
—CNBC's Julia Boorstin contributed to this report.