Evidently miscreants were able to hack into the FBI email system. Immediately a spam campaign was launched showing legitimate email servers accounts but without the usual FBI message signatures.

The FBI confessed to the incident. The system is public facing and used for nonclassified public messages.

Evidently several hundred thousand messages were sent, before the agency was able to put a stop to it. The person’s motives are unknown, and it was not immediately clear the extent to which the hacker gained access to the FBI’s email system. The email message was a bizarre, technically incoherent warning that made reference to cybersecurity writer Vinny Troia as well as a cybercriminal group called The Dark Overlord.

The FBI routinely warns American companies of cyber threats targeting particular industries, or when they learn of malicious hackers trying an effective new technique. This is believed to be the first known case of a seemingly malicious actor gaining access to one of those systems to send spam to a large number of people.