But the hackers called for others to carry on. "For the past 50 days we've been disrupting and exposing corporations, governments, often the general population itself, and quite possibly everything in between, just because we could," said the group in a statement uploaded to pastebin. "We hope, wish, even beg, that the movement manifests itself into a revolution that can continue on without us."
But why might its members have suddenly decided to bow out? According to security experts, the group may have decided to move on due to increasing pressure from law enforcement agencies. Notably, authorities in Britain last week arrested 19-year-old Ryan Cleary, who had been linked to LulzSec. But the group said via Twitter that Cleary was only "mildly associated" with the group.
"Maybe, quite simply, LulzSec was worried that the heat was intensifying--and it was time for them to get out of the kitchen before the computer crime authorities caught up with them," said Graham Cluley, senior technology consultant at Sophos, in a blog post.
But at least some of the group's six members already appear to be continuing their work elsewhere, and combating criticism from other hackers that they'd cut and run. Notably, the LulzSec member known as Sabu said via Twitter on Monday that "we didn't 'run' we are in fact online @ irc.anonops.li." In addition, said Sabu, "We retired lulzsec at its peak. We are smart."
Regardless, after LulzSec announced its exit, the hacker underground didn't suddenly go silent. Indeed, on Sunday, the hacking collective known as Anonymous--from which LulzSec was rumored to have sprung--released a 625-MB file containing an ISO archive file (disc image) containing the Cyberterrorism Defense Initiative Sentinel Cyberterrorism Defense Program.
On Saturday, as noted, LulzSec also released a final cache of numerous documents via BitTorrent, including details on AT&T's forthcoming wireless network rollout, evidence LulzSec had hacked into a U.S. Navy job search website, the username details for 550,000 people who signed up to play a Battlefield Heroes videogame beta, 50,000 user credentials from "random gaming forums," details on 200,000 users of Hackforums.net, and details on 12,000 NATO bookshop users, amongst other information. That followed LulzSec's release, on Thursday, of numerous internal Arizona law enforcement documents, in protest against the state's controversial immigration laws.
Does LulzSec's nonstop hacking campaign, and apparent success at taking down everyone from Sony to the U.S. Senate, point to fundamental flaws in website security? "One of the assertions made by the recent run of high profile attacks was that all networks are vulnerable, and the groups behind these attacks either had or could have access to many more systems if they wish," said the SANS Technology Institute's Johannes B. Ullrich in a blog post. "I would like to question the conclusion that recent attacks prove that all networks are vulnerable, as well as the successful attacks [prove] a large scale failure of information security."
For starters, LulzSec only publicized its successful attacks. Furthermore, he said, no information security program can prevent every possible breach. "As an information security professional, it should be your goal to mitigate risks to a level that is small enough to be acceptable to business. It is much more about risk management then avoiding every single risk," he said. "With that focus on risk management, information security itself becomes a solvable problem."
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