Experts on a cryptography panel at the RSA conference reject the idea of the U.S. government holding encryption keys.
Both operations required coordination between government agencies and private sector partners.
A recent survey found that 55 percent of organizations that have been hit by such attacks recommend negotiating with cybecriminals to restore data.
The attack exploits an old ActiveX vulnerability, according to Symantec researchers.
The airline says tens of thousands of accounts were accessed.
The North Korean government called the accusation 'a false judgement by an idiot.'
Two separate hacker groups recently threatened to release sensitive data unless ransoms were paid.