The dearth of details from Sony about a criminal intrusion into its PlayStation Network is fomenting plenty of speculation about the methods and motives behind the attackers, and some of it isn't pretty.
The most dire scenario is that attackers gained, or tried to gain, control of the part of Sony's network that issues updates for the PlayStation 3. If that were to happen, the attackers could use the private key uncovered late last year by the fail0verflow hacker collective, and independently published around the same time by jailbreaker George Hotz, to sign malicious firmware updates offered to tens of millions of console owners.
In 2008, researchers effectively created their own rogue certificate authority by harnessing the massive computing power of just 200 PS3s to find so-called collisions in MD5, a cryptographic hash algorithm with known weaknesses. With an army of literally millions of zombie PS3s under their control, hackers would own a supercomputer at par or superior to those possessed by most nation states, and they wouldn't even have to foot the power bill.
“It's really scary,” said Marsh Ray, a researcher and software developer at two-factor authentication service PhoneFactor, who fleshed out the doomsday scenario more thoroughly on Monday. “It's justification for Sony freaking out. They could lose control of their whole PS3 network.”
Ray's speculation is fueled in part by chat transcripts that appear to show unknown hackers discussing serious weaknesses in the PSN authentication system. In it, purported hackers going by the handles trixter and SKFU discuss how to connect to PSN servers using consoles with older firmware that contain bugs susceptible to jailbreaking exploits, even though Sony takes great pains to prevent that from happening.
“I just finished decrypting 100% of all PSN functions,” SKFU claimed.
There's no evidence the participants had anything to do with the massive security breach that plundered names, addresses, email addresses, passwords and other sensitive information from some 77 million PSN users. But the log did raise questions about the security of the network, since it claimed it was possible to fool the PSN's authentication system into permitting rogue consoles.
What's more, the hackers discussed ways to use a modified version of Moxie Marlinspike's SSLSniff on modded PS3s to defeat SSL encryption that protects communications between the PSN and the console.
Around the same time the chat log came to light, a PS3 user blogged about Rebug, which he described as a piece of custom firmware that converts retail consoles into developer consoles with significantly more options. Once again, there's no evidence the PS3 user, who went by the name chesh420, had anything to do with the breach, but he claimed the modded machines were able to engage in “extreme piracy of PSN content” by bypassing the network's authentication system.
Researchers speculating on the cause of the PSN breach are reading the posts as evidence that it may be possible to override Sony's security using modded PS3s, particularly if it was premised on the assumption that it was impossible for jailbroken consoles to access the network.