The Federal Bureau of Investigation (FBI) email servers were hacked to distribute spam email impersonating FBI warnings that the recipients' network was breached and data was stolen.
The emails pretended to warn about a “sophisticated chain attack” from an advanced threat actor known, who they identify as Vinny Troia. Troia is the head of security research of the dark web intelligence companies NightLion and Shadowbyte....
https://www.bleepingcomputer.com/news/security/fbi-system-hacked-to-email-urgent-warning-about-fake-cyberattacks/
from BleepingComputer