Anthony Scaramucci fell victim to an increasingly popular form of email trickery during his brief tenure as White House communications director.  (Wikimedia Photo / Jdarsie11)

It was easy to impersonate White House officials like Jared Kushner and Reince Preibus or even Eric Trump. It fooled plenty of people who should have known better, like now-former White House communications director Anthony Scaramucci; former Utah governor and presidential candidate Jon Huntsman; Homeland Security Adviser Tom Bossert; and Eric Trump, too.

This email prankster hoax is embarrassing for the White House, but it’s not funny.

Now you know why financial institutions and critical infrastructure systems are at such great risk. Millions of dollars in security investments still can’t solve the riddle of the human element.

In case you missed it, assorted members of the Trump White House were mortified last week when it was revealed that an email prankster using basic impersonation strategies duped them into private conversations. The start-studded list of “victims” included the now-deposed Scaramucci  — who was tricked into a fake conversation with someone he thought was Preibus, the now-former White House chief of staff.

The technique was easy. The prankster is a U.K.-based designer who started pulling stunts like this earlier this spring. At that time, he successfully targeted big-name banking executives, like Barclays CEO Jes Staley. He uses the Twitter handle @Sinon_Reborn, a tip of the cap to Greek mythology.

The prankster simply registers email accounts like Reince.Preibus@mail.com and starts sending messages. In the case of Scaramucci, he fell for the hoax, hook, line and sinker.

In one part of the dialog, the fake Preibus said, “The way in which that transition has come about has been diabolical. And hurtful. I don’t expect a reply.”

Scaramucci, believing the message was authentic, responded: “You know what you did. We all do. Even today. But rest assured we were prepared. A Man would apologize.”

CNN first reported on the exchanges, which the hoaxster had already made public on his Twitter feed.

The hoax exploits an age-old problem with the way the Internet was built: It’s pretty easy for people (and computers) to lie about who they are and where they are.

And while this attack is funny, it’s just a form of something that’s rampaging through the business world right now – executive ID theft.  Workers around the globe are falling for fake emails like this and taking real steps that cost millions. The FBI has called the crime – which goes by the pedantic name “business email compromise” – one of the fastest-growing digital cons. In an SEC filing in 2015, one technology company reported that it had been hit by a con that led to “transfers of funds aggregating $46.7 million.” In one version of the crime, the fake executive sends an urgent message asking that money be wired to close an international business deal. Given the power relationships involved, assistants often comply.

This week’s hoax just shows how easy it can be. The White House prankster didn’t need to spoof his address or use any mildly technical tricks. He just opened an email address using someone else’s name.

Despite constant reminders to the contrary, most people implicitly trust their technology and impulsively open emails that seem to be from friends and associates.  The hotter the potential exchange, the more victims let their guard down. That’s why people rush to open emails with subject lines like “Someone has your password.” In case you’ve forgotten, that’s how John Podesta’s email was hacked.

The White House prankster didn’t immediately respond to my requests for comment, but he has said previously he’s merely committing an act of protest.

His beef with banks began over a loan dispute, followed by frustrations with slow customer service, and finally criticism of Barclays efforts to unmask a whistleblower.

He said on Tuesday morning that he would stop targeting Washington D.C. officials now.

Anyone reading this story should realize two things: First, criminals and pranksters alike are constantly trying to trick you into reading emails and clicking on things you shouldn’t. We should all know better, but we don’t. We all have moments of weakness.

Second: Given the high-profile success of the prankster, you should expect a lot of copycats now.

There are technology solutions that can help with the problem.  Some email clients now come with a warning when an email does not come from someone in your address book, or the sender might be inauthentic. Those solutions are clunky, however, and users often blow past the warnings. It’s not a bad idea to look at headers of email senders, particularly if something seems unusual about the message.

But the only real firewall for tricks like this is the one between your ears. Emails are very, very insecure, and will remain that way for a long time. Slow down. Suspect everything, even if it seems to come from a friend. Never click on links in email, period.

In short, don’t trust.

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