The White House said Thursday that the cyberattack against Sony is a "serious national security matter" that needs a "proportional response."
White House spokesman Josh Earnest discussed the Sony hack during a Thursday briefing, saying it was a "destructive activity with malicious intent that was initiated by a sophisticated actor."
In addition to calling the hack a matter of national security, Earnest also said U.S. leaders "would be mindful of the fact that we need a proportional response."
Although Earnest said there are "a range of options" currently under consideration, he did not go into more detail about what they were.
He also cautioned that "sophisticated actors" — such as foreign governments — could be seeking to provoke a response from the U.S. and use it to their advantage.
U.S. officials, he said, would be "mindful of the fact that sophisticated actors, when they carry out actions like this, are oftentimes ... seeking to provoke a response from the United States of America.
"They may believe that a response from us in one fashion or another would be advantageous so them. And so we want to be mindful of that too."
The briefing came a day after sources in the U.S. government said North Korea was in some way responsible for the cyberattack.
Other countries may have helped North Korea pull off the attack.
Earnest said Thursday that the investigation was progressing and Obama is monitoring the situation. Obama scheduled a Friday news conference and according to CNN, the U.S. is planning to lay blame for the hack.
Meanwhile, other nations began to emerge as possible accomplices to North Korea. Both Reuters and Fox News reported Thursday that Iran may have helped in the hack. The network also reported that China and Russia may be suspects as well.
News also trickled out Thursday about the methodology used in the hack.
A cybersecurity expert in Tel Aviv told BuzzFeed News the attack was a "cut and paste" job that used widely available malware.
Fox News further reported that the malware both overwrites data and disrupts a computer's ability to function. The damage can be so extensive that data is permanently lost.
Investigators also believe the hackers may have initially infiltrated Sony's computers by stealing the credentials of a system administrator, CNN reported. With those credentials, the hackers would have been able to gain broad access to Sony's systems.