Avraham Eisenberg Sentenced to 52 Months in Prison for Child Porn Following Karlstack Investigation

Three years ago, I exclusively exposed Avraham Eisenberg as the hacker who exploited the Mango Markets crypto protocol for a nine-figure payday.

EXCLUSIVE: The Man Who May Have Milked $100+ Million from Mango Markets

Avraham, then living in San Juan, Puerto Rico, fled to Israel the very day I outed him—where he was shielded from extradition to the U.S.

The very next week, one of Avraham’s associates, Nikolai Mushegian, 29, who also lived in Puerto Rico, tweeted that ‘‘CIA and Mossad and pedo elite are running some kind of sex trafficking entrapment blackmail ring out of Puerto Rico ... They are going to frame me with a laptop planted by my ex [girlfriend] who was a spy. They will torture me to death.’’

A few hours after sending this tweet, Mushegian’s corpse washed up on Condado Beach, fully clothed, face down. No foul play was ever determined in his death.

I share this not for shock value, but to give you a sense of the world Avraham operated in—and the risk I took in going after him. But some things are more important than personal safety.

Two months later, in December 2022, Avraham Eisenberg flew back from Israel to Puerto Rico, at which point he was arrested by the FBI upon stepping foot on American soil. Nobody initially knew why he would foolishly fly back to America, but I heard through the grapevine the the reason he came back to America was to get the last few days of physical presence in Puerto Rico needed for tax residency. Apparently his lawyer told him it would be fine, lol.

BREAKING: FBI Arrests Mango Markets Exploiter Following Karlstack Investigation

Upon arrest, the FBI discovered 1,274 items of CSAM on his electronics devices, including ‘‘a young corpse.’’

In May 2025—just a few weeks ago—Avraham Eisenberg was sentenced to 52 months in federal prison after pleading guilty to possession of CSAM. This was first reported by Inner City Press, a court reporter in New York who attended the trial.

Avraham Eisenberg

This post is, in part, a victory lap. Hundreds of my subscribers found my work through that investigation, and you deserve an update on how it ended. I’m immensely proud of the role my reporting played in bringing him down. If I accomplish nothing else in my career, taking down Avi will have been worth it.

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