There's nothing stopping attackers from manipulating the data they make public.
In the past few years, the devastating effects of hackers breaking into an organization's network, stealing confidential data, and publishing everything have been made clear. It happened to the Democratic National Committee, to Sony, to the National Security Agency, to the cyber-arms weapons manufacturer Hacking Team, to the online adultery site Ashley Madison, and to the Panamanian tax-evasion law firm Mossack Fonseca.
This style of attack is known as organizational doxing....
Continue reading: http://www.theatlantic.com/technology/archive/2016/09/hacking-forgeries/499775/
Schneier, Bruce. “How Long Until Hackers Start Faking Leaked Documents?.” The Atlantic, September 13, 2016