Gregory D. Evans | Ex-Hacker | TV Personality | Author

The FBI on Thursday arrested a member of the hacking group LulzSec for his alleged role in the hacking of Sony Pictures Entertainment.

Cody Kretsinger, a 23-year-old Phoenix resident, was arrested this morning by the FBI after a district court in Los Angeles handed down a sealed indictment on Sept. 2. He is charged with conspiracy and the unauthorized impairment of a protected computer. The indictment was unsealed after his arrest.

In June, hackers associated with LulzSec hacked into SonyPictures.com and compromised the personal information of more than 1 million users. While the group did not copy the information of all 1 million people due to financial restraints, it did access thousands of records, and Sony Pictures was later required to notify 37,500 users that their personal information might be at risk.

Sony’s PlayStation Network was also the victim of a massive cyber attack earlier this year. Sony suggested that Anonymous was behind the attack, but Anonymous denied it.

Kretsinger, who is known as “recursion” online, used a proxy server to hide his IP address while carrying out the Sony Pictures hack, the FBI said. He eventually gained access through a SQL injection.

The indictment accuses Kretsinger and his cohorts of stealing information from Sony’s Web site, posting it online, and taking credit for it via Twitter. The FBI said Kretsinger then erased the hard drive of the computer he used to hack the Web site.

Kretsinger appeared in a Phoenix court today, where the FBI requested that he be transferred to Los Angeles. If convicted, he faces up to 15 years in prison.

In a blog post, security firm Imperva said Kretsinger and other Anonymous and LulzSec hackers who have been arrested recently made two critical mistakes: they brought too much attention to themselves and they didn’t cover their tracks.

“If you look at hacking historically, over the past 20 years many of the high-profile attacks or those that involve serious losses to governments or commercial companies have ended up with law enforcement finding the perpetrators eventually,” the company said.

Earlier today, one of the Anonymous feeds tweeted, “We roll our many eyes while asking: You can arrest as many as you want. It will not make the symptom go away. Neither the problem.”

LulzSec emerged earlier this year and quickly wrestled the headlines away from another major hacking group, Anonymous, perhaps due to the juvenile and taunting nature of many of its tweets. Everyone was a target and very few things were off limits; at one point, the group opened up a hotline where it took hacking requests. LulzSecfirst got noticed, however, when it hacked the Web sites of Fox.com and PBS. It stole Fox employee passwords and posted them online and took over the Twitter account of a Fox affiliate. It then did the same with various targets before suddenly disbanding, possibly due to heat from the authorities. LulzSec members have popped up here and there since then in the name of “AntiSec,” a joint LulzSec-Anonymous effort against governments with which they disagree, but they have largely ceded power back to Anonymous.

Fox News, meanwhile, reported that the FBI also arrested a homeless man in San Francisco who was reportedly involved in a hack of the Santa Cruz government Web site.

For more, see PCMag’s guide to knowing your hackers as well as the “Who Is LulzSec?” slideshow below.

For more from Chloe, follow her on Twitter @ChloeAlbanesius.

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