Hacker-Turned-Informant to Be Freed After Helping Feds

May 27, 2014 — -- A hacker who aided in high-profile attacks against governments and corporations, and later flipped to use his cyber skills for the FBI, will be freed from prison, a New York court ordered today.

The hacker, whose real name is Hector Xavier Monsegur but who is known online as Sabu, pleaded guilty three years ago and agreed to assist the FBI. In exchange, prosecutors requested leniency and their sentencing memo revealed, for the first time, the extent of his cooperation.

Monsegur helped the FBI "disrupt or prevent at least 300 hacks" against the military, Congress and "several private companies," prosecutors wrote, adding that “Monsegur’s actions prevented at least millions of dollars in loss to these victims.”

The specific targets were redacted but included divisions of the federal government, the military, Congress, NASA, a television network, a security firm, a video game manufacturer and a water utility for an American city.

“The amount of loss prevented by Monsegur’s actions is difficult to fully quantify but even a conservative estimate would yield a loss prevention figure in the millions of dollars,” said James Pastore, an Assistant U.S. Attorney for the Southern District of New York. “Moreover, Monsegur provided information about actual and purported vulnerabilities in critical infrastructure.”

Prosecutors also said Monsegur “contributed directly to the identification, prosecution and conviction of eight of his major co-conspirators,” including Jeremy Hammond who, at the time of his arrest in 2012, was the FBI’s number one cyber-criminal target.

Monsegur himself has been a target. In the last three years the FBI relocated him and certain members of his family after he was “approached on the street and threatened or menaced.”

A one-time member of prominent hacking groups Anonymous, LulzSec and InternetFeds, Monsegur attacked the websites of Visa, MasterCard and PayPal in 2010 over their refusal to process donations to WikiLeaks. He also hacked Sony, PBS, the U.S. Senate and what prosecutors called a number of other “significant criminal computer intrusions.”

Monsegur was sentenced by Judge Loretta Preska to time already served – some seven months.

In pronouncing the sentence, Judge Preska said Monsegur’s cooperation was “truly extraordinary.”

"The fact that Monsegur immediately chose to cooperate and went back online... allowed the extraordinary cooperation," she said.

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