re the ex-FBI guy quoted by McClatchy, Leo Taddeo:
he was being quoted in this 5-journo Bloomberg piece in Sept, which also involved Schneiderman. as an aside, from what I can gather, Taddeo used to work out of NYC, at some stage.
9 Sept: Bloomberg: One Thing Government Agrees on: Equifax Deserves a Grilling
By Elizabeth Dexheimer, Chris Stroh, and David McLaughlin
With assistance by Arit John, and Todd Shields
New York Attorney General Eric Schneiderman’s office said in a statement that it had opened an investigation into Equifax because the hack had affected more than 8 million New Yorkers...
Although Equifax said the attack was carried out by criminals, the FBI will work to determine if there are also “potential national security implications” such as involvement by agents of a foreign government, said Leo Taddeo, a former FBI special agent who led cybersecurity investigations.
“It’s hard to tell the difference these days between an intelligence operation and a criminal operation,” said Taddeo, now chief information security officer for Cyxtera Technologies Inc...
https://www.bloomberg.com/news/articles/2017-09-08/one-thing-all-of-government-agrees-on-equifax-deserves-grilling
... planted a “poison pill” during the DNC hack. He placed a string of numbers that are his Russian passport number and the number of his visa to visit the Caribbean island of St. Martin in a hidden .dat file...
No hacker is going to “sign his work”. That would be idiotic. The best hack is one which leaves no evidence of ever having occurred. Even better is the hack which allows continued surveillance of the server unbeknown to the owner of the server.