Hacker Group Targets Financial Information of Over 100 Companies: FireEye

San Francisco-based FireEye said the mysterious group, dubbed FIN4, showed deep familiarity with the way businesses work and appeared to target the accounts of officials with knowledge of merger and acquisitions and other valuable corporate secrets.

Based on information from its corporate security clients, FireEye said FIN4 has gone after access to email accounts of companies' top executives, legal counsel, outside consultants and researchers.

Some two-thirds of the companies FIN4 has targeted since mid-2013 are in the pharmaceutical and healthcare industries, where there has been a surge of large deals in the past year, FireEye said.

FireEye said most of the victim companies are publicly listed, though it would not divulge their names, citing client confidentiality.

"FIN4 knows their targets," the FireEye report said.

"We can only surmise how they may be using and potentially benefiting from the valuable information they are able to obtain.

"However one fact remains clear: access to insider information that could make or break stock prices for dozens of publicly traded companies could surely put FIN4 at a considerable trading advantage."