White House Senior Adviser Jared Kushner’s lawyer was punked by an email hoaxer on Monday. (Alex Brandon/AP)

First it was presidential son Eric Trump. Then Jon Huntsman Jr., the Russian ambassador-designee. Former White House communications director Anthony Scaramucci was fooled twice. Even homeland security adviser Tom Bossert, an expert in cybersecurity, fell for the electronic flimflam.

On Monday, a British email prankster added a new name to his ever-expanding list of the prominent people he’s punked: Jared Kushner’s lawyer, Abbe Lowell.

Posing as the president’s son-in-law, the prankster asked Lowell in an email whether he should delete some “adult content” that was on his private email account as a result of “some exchanges” with a website.

“I’m so embarrassed,” the fake Kushner emailed the lawyer. “It’s fairly specialist stuff, half naked women on a trampoline, standing on lego scenes, the tag for the movie was #standingOnTheLittlePeople.”

Lowell took the matter seriously, perhaps a wise idea given that Kushner is wrapped up in Robert S. Mueller III’s investigation of the Trump campaign’s alleged ties to Russia and because Kushner is one of six senior White House aides whose use of private email accounts for official business just came to light. So Lowell judiciously advised his “client” not to delete the material and “don’t send to anyone.” (Lowell declined to comment).

The email prankster — who goes by the nom-de-hoax “@Sinon_Reborn” on Twitter — has been having gentle fun with the mighty since May. He began by duping a series of British banking executives, including the governor of the Bank of England, into making unguarded comments to an email sender they thought was a colleague. He tricked a Labour official, Diane Abbott, into revealing that she has diabetes.

Turning to America, Sinon — the name refers to the Greek warrior who persuaded the Trojans to accept the wooden horse — pretended to be White House chief of staff Reince Priebus and then Huntsman to fool Scaramucci. (Huntsman holds the distinction of both being scammed and being impersonated in Sinon’s hoaxes.) The prankster hoodwinked Eric Trump into thinking that he was his brother, Donald Trump Jr., until Eric Trump caught on and responded, “I have sent this to law enforcement who will handle from here.”

In August, he posed as former White House chief strategist Stephen K. Bannon in an exchange with Breitbart News editor Alexander Marlow. The two bantered a bit before Marlow responded by passing off a disparaging rumor about Ivanka Trump and Kushner’s marriage, and his prediction that the couple would be out of the White House by Christmas.

(Marlow, in an interview, says he was ahead of the curve. Considering Kushner’s advice to Trump to back a losing Alabama Senate candidate, Luther Strange, Marlow said he expects Kushner to leave soon: “I think my timetable [for his departure] was a little long. Now I look more prescient.”)

Although he prefers to remain anonymous, Sinon doesn’t hide all that much about himself in a phone interview. If what he says is to believed, he is 39 years old, lives in Manchester, England, and has worked for advertising agencies as a web designer. He has two cats and is currently unemployed.

Sinon said he used to support conservatives but has “mellowed” and now leans left. “I generally think of myself as being a nice person and not a selfish a------, which there seem to be a lot of in Washington.”

But he’s also quick to say that he means no harm, that he’s just in it for the laughs. He doesn’t want to steal secrets or even to make news, he said. The revelation of Abbott’s diabetes, for example, made him uneasy.

“I’m not looking for the keys to vault,” he said. “I try to put an ethical and moral framework around what I do. If I went out there to expose huge lies, I’d be shut down quickly indeed. This way gives it longevity. It’s throwaway stuff. The victim is likely to wake up the next day and not care.”

As silly as his stunts can be, there’s a serious underlying point about modern communications. Sinon trades on trust and the sheer sensory overload of everyday digital communications. His emails come from accounts that upon closer inspection might look sketchy — would Jared Kushner really communicate from “kushner.jared@mail.com”? — but nobody bothers to look closely. They merely assume an email with a friend or colleague’s name on it is from that sender.

Sinon says it’s not hard to figure out someone’s email address; he’ll sometimes try as many as 20 different combinations (first name dot last name, etc.) to reach a prominent person. It’s also not difficult to mimic the phrases and tone of prominent Americans.

Still, some targets have been tough. His attempts to engage officials at Fort Knox were met with no reply; one banker caught on early and replied, “Nice try.” He’s also been unable to reach the biggest target of all — “the golden egg,” as he puts it — President Trump, quite possibly because Trump is said not to use email.

Sinon said he’s not worried about any legal jeopardy for his pranks, despite laws against “catfishing,” or impersonating someone online. He is also unmoved by White House press secretary Sarah Huckabee Sanders’s comment after one of his pranks in August, in which she warned, “We take all cyber-related issues very seriously and are looking into these incidents further.”

Sinon’s rationalization: No one would sue him or press charges because they would “look stupid twice” by taking him to court over mild personal embarrassment, if any.

So watch your inbox. “My one big plan is to have no plan,” he said. “I embrace the chaos and will keep rolling along with it. . . . I’ll be keeping the cape on for a while.”