John Draper , a legendary figure in the world of pre-digital phone hacking known as "phreaking," has been publicly accused of inappropriate sexual behavior going back nearly two decades.

According to a new Friday report by BuzzFeed News, Draper, who is also known as "Captain Crunch," acted inappropriately with six adult men and minors between 1999 and 2007 during so-called "energy" exercises, which sometimes resulted in private invitations to his hotel room. There, Draper allegedly made unwanted sexual advances.

As a result of the new revelations, Draper, 74, is now no longer welcome at Defcon. Michael Farnum, the founder of HOU.SEC.CON, told Ars on Friday afternoon that Draper, who had been scheduled to speak in April 2018, was disinvited.

In conjunction with others in the late 1960s and early 1970s, Draper figured out that a toy whistle given out in boxes of Cap'n Crunch cereal emitted a tone at 2600 Hertz. By pure coincidence, that happened to be the tone AT&T used to reset its trunk lines. As a result, Draper became a legend in the nascent world of phone phreaking, a predecessor to early personal computer hacking. He was profiled in a lengthy October 1971 Esquire article.

Draper helped popularize the "Little Blue Box," which created the same tone as the whistle—a later version was sold by Steve Jobs and Steve Wozniak, who went on to found Apple.

BuzzFeed also reported that "through a spokesperson," Draper refused to answer any questions.

Draper is currently promoting a new memoir, called "Beyond the Little Blue Box," which raised nearly $30,000 on Kickstarter. Draper’s co-author, Craig Wilson Fraser, did not immediately respond to Ars’ request for comment. Draper’s book publicist, Allie McKay, also did not immediately respond to Ars’ query.

Speak up, speak out

For the last ~40 or so years, every time I see Draper's name lauded in print or on the net it brings back some disturbing memories. Fortunately, my story is not as bad as it could have been, but I regret not telling it more publicly sooner. 1/ — matt blaze (@mattblaze) November 18, 2017

In a series of tweets, Matt Blaze, now a well-known cryptography professor at the University of Pennsylvania, said on Twitter that Draper took an interest in him as a teenager, and invited him to share in his "exercises."

Per BuzzFeed News, one such reported incident also came from 2000, where Ethan Smith, then a 29-year-old reporter for the now-defunct Industry Standard was attending the Hackers On Planet Earth conference. Smith met and was trying to interview Draper, who invited him up to his hotel room.

There, Draper began massaging Smith’s thighs and then if he could climb on Smith’s back. He agreed.

"He climbs on my back, wants me to give him a piggy back ride, carrying him up and down in the room," Smith told BuzzFeed. "I’m still not getting what’s happening. I could feel he had an erection, that he was grinding against my back."

That time I tried to interview John Draper, the hacker better known as Captain Crunch, and instead he sexually molested me. https://t.co/MVbyGkR5az — Ethan Smith (@ethanwsj) November 17, 2017

Smith soon left and didn’t end up interviewing Draper. Smith, who is now the Los Angeles bureau chief at the Wall Street Journal, told Ars that he didn’t tell anyone about his incident with Draper "for many years, and in retrospect I guess I wish I had."

"I think I went through a similar process that you would see described by a lot of people where I felt embarrassed and responsible and didn’t really have any idea how persistent how he was being," Smith said.

"If nobody is speaking out about it, nobody knows how widespread it is. Nobody knows that he was doing this allegedly with underage boys, and those are reasons that it would be good to speak out."

Since BuzzFeed News began its reporting on Draper, the website for his book has been updated to include an announcement that Draper was diagnosed with Asperger’s in 2008 and has displayed "immature behavior." The website also notes that as a result, Draper and his book’s "team" are donating to The Autism Society in the US and Action for Aspergers in the United Kingdom to support their activities.

"Each charity will receive 5% of our profits for the fiscal year following the kickstarter campaign, and will share a $2600 cash donation in March 2018," the group said in the statement.

The Autism Society did not immediately respond to Ars' request for comment.

Meanwhile, Elaine Nicholson, the CEO of Action for Asperger's said until her organization was contacted by Ars, she was entirely unaware of Draper and had "no prior knowledge of this."

"If an abuse of children is involved, we do not want any involvement with anyone or any organization alleged or proven to have done such deeds," she e-mailed. "We do not know this man, and certainly will not and cannot accept any donations from him if his character is truly tarnished and lives have been injured as a result. I hope I have made our position very clear."

UPDATE Monday November 20 7:39pm ET: Matt Asner, the vice president of development at the Autism Society of America, wrote to Ars.

"We do not know of John Draper who is alleged to have been sexually inappropriate," he e-mailed. "Mr. Draper never asked for us to approve him giving us any money from his book sales. To date, we have received none. Of course, we strongly believe that what Mr. Draper is alleged to have done must never be accepted and if he is proven guilty of such allegations, he must be fully punished as provided for by law. If we receive any funds from Mr. Draper's book, we will either turn them back to Mr. Draper or use them to support programs that help individuals with autism who have been sexually abused."