Sony didn't notice the security breaches that compromised user accounts on the PlayStation Network, Qriocity and Sony Online Entertainment because it was distracted by distributed denial of service attacks, the company said in a letter to Congress.
Several Sony divisions had been hit by a large-scale coordinated denial-of-service attack in early April from the Anonymous hacker collective protesting the company's lawsuit against George Hotz, a PlayStation 3 hacker, Sony wrote in a letter to the United States House of Representatives on May 4. The combined effect of the DDoS attack and the sophisticated methods used by the cyber-thieves made it difficult for Sony's administrators to detect the data breach, according to the letter.
Sony disclosed on April 26 that thieves had stolen account information of up to 77 million users on the PlayStation Network and Qriocity. A week later, the company admitted on May 2 that the Sony Online Entertainment gaming service had also been breached, affecting an additional 24.6 million users. About 101 million user accounts have been compromised to date. The stolen data included names, addresses, email addresses, dates of birth. Some credit card information may have been stolen, but Sony claimed the numbers was securely saved as a cryptographic hash.
"Security teams were working very hard to defend against denial of service attacks, and that may have made it more difficult to detect this intrusion quickly," Sony Computer Entertainment chairman Kazuo Hirai wrote in the letter.
The cyber-criminals exploited a system software vulnerability to gain access into the network while Sony's security teams were focused on deflecting the DDOS attacks, according to the letter. Forensics investigators determined the intruders used highly sophisticated and aggressive techniques to break in, hide their presence and escalate privileges inside the servers. "The intruders deleted log files in order to hide the extent of their work and activity within the network," the chairman wrote.
The House Committee on Energy and Commerce held a hearing on May 4 to address data theft and consumer impact. Sony declined to appear at the hearing, but sent an eight-page letter detailing what had happened and what it was doing to resolve the issue to the Subcommittee on Commerce, Manufacturing and Trade.
"Whether those who participated in the denial of services attacks were conspirators or whether they were simply duped into providing cover for a very clever thief, we may never know," Hirai wrote.
A segment of Anonymous launched Operation Sony on April 2 to protest Sony suing George Hotz for publishing code that lets users jailbreak the PlayStation 3. The case was settled out of court and George Hotz agreed to take down his site on April 11. Dissatisfied members declared April 16 a day of protest for Sony and organized a 24-hour, in-store boycott at Sony stores around the world. A video message warned, "Prepare for the biggest attack you have ever witnessed, Anonymous style."
Cyber-attackers breached PSN, SOE and Qriocity between April 16 and April 17, Sony said.
"Those who participated in the denial of service attacks should understand that - whether they knew it or not - they were aiding in a well planned, well executed, large-scale theft that left not only Sony a victim, but also Sony's many customers around the world," Hirai wrote. Anyone can join an Anonymous-coordinated DDoS campaign, as its "Low Orbit Ion Cannon" attack software is readily available for download. Once installed, the user just clicks on "Fire" and the software sends network packets to the target Website.
Sony is not yet saying that the two cyber-attacks were coordinated, just that they happened around the same time.
Anonymous officially denied any involvement in the PSN breach, posting a press release entitled, "For once we didn't do it," in April. It acknowledged that "other Anons" could have acted by themselves.
"We are trying to fight criminal activities by corporations and governments, not steal credit cards," a according to an official press released published May 4.
In Sony's letter addressed to Reps. Mary Bono Mack and G.K. Butterfield, the company said it has enhanced data security and encryption on its systems and added automated software monitoring since the breaches. It had hired multiple security firms and forensic teams to determine the scope of the breach.