Most victims of targeted persistent threat (APT) attacks have been under siege for so long by the time they discover it that forensics investigators can’t even trace original machine that was infected. The biggest shift during the past year is the volume of these attacks and the wider scope of industries being targeted. In the past 18 months, 42 percent of these victims were commercial firms, with 10 percent representing 10 percent of that sector. “All you’ve done by sharing is change the fingerprint and made the problem worse,” Kevin Mandia says.”]
Source: https://www.darkreading.com/attacks-breaches/an-advanced-persistent-threat-reality-check