Security analysts have narrowed down the probable causes of the infamous Sony PlayStation Network breach.
Sony is slowly restoring its PlayStation Network and Online Entertainment service following a hack that exposed the personal details of 77 million PlayStation Network gamers and (separately) 25 million customers of its Online Entertainment services. Personal information including names, email addresses, dates of birth and phone numbers was disclosed by the PlayStation Network hack.
The deep penetrating cyber assault against Sony followed shortly denial of service attacks against the entertainment giant (codenamed OpSony) by members of Anonymous as part of a protest against legal action by the entrainment giant against PlayStation modders, such as George Hotz. Hotz released a root key that allowed users to sign and run any code they wanted on their PS3 back in January.
Sony responded with a lawsuit alleging violations of the DMCA and Computer Fraud and Abuse Act against Hotz and others. Anonymous fired up its DDoS attack canons in early April. More than a fortnight later Sony detected an intrusion, and responded by taking its PlayStation Network and Qriocity servers offline.
Sony held a press conference on the intrusion on 1 May during which the Japanese firm gave limited details on what might have happened, suggesting the database server might have been accessible via some sort of SQL injection exploit. Application security firm VeraCode is less than satisfied with this theory, coming up with a variety of scenarios it reckons are more plausible explanations about what went wrong.
Among the theories it considers is an attack based on physical access to critical systems during the time Sony moved its servers. That sounds unlikely. What's more plausible is that one of the 205 SOE employees made redundant at the end of March might have used their access to attack Sony in retaliation for their dismissal. The Anonymous attacks would have acted as a smokescreen diverting attention from their actions in this scenario.
Unpatched servers might also be behind the attack. A chat log of several PS3 modders probing PSN has appeared online, claiming that some of PSN’s webservers were running outdated versions of Apache and Linux. "It is a solid bet that if those packages were outdated, the rest of the server hadn’t been patched in the last 5 years either," Veracode notes. "If that was the case, then the intrusion would have been as simple as firing up Metasploit and going to work. As a side note, Google’s web cache shows that Sony’s servers were up to date, so this whole theory may be bunk."
Thanks to the PS3 modding work, Rebug custom firmware was released in March that allowed access to many of the features only found in PS3 developer kits, which typically cost more than $10,000. VeraCode theorises that this Rebug firmware might have played a key role in using a PS3 console to hack into the PlayStaion Network, a theory supported by fragments of circumstantial evidence.
"One of the interesting features of the Rebug firmware was the ability to switch which set of PSN servers the console connected to," VeraCode explains. "For instance, in one attack modders found it was possible to force a PS3 to connect to the prod-qa instance of PSN."
"On this particular instance, the servers would not authenticate credit card information before adding credit to the account, so attackers could simply add unlimited credit for the PSN store. Much of this information was publicly available before the breach happened. Also an IRC chat log claimed that there were 45 Internet accessible PSN instances at the time of the breach. It is possible that one of the PSN instances meant for internal use only had certain flaws or was configured in such a way that a rogue PS3 could have leveraged it against the rest of Sony’s network."
(El Reg raised this very possibility a few weeks ago.)
VeraCode concludes that a vulnerability in an application was the initial vector of the breach and that this vulnerability may have either been on Sony's servers or elsewhere. "It looks like a vulnerability in an application was the initial point of entry for this breach. Whether or not this was done using a modified PS3 is up for debate, and there isn’t any solid proof one way or another," VeraCode notes, adding that it's more likely that Sony has been responding to "a slew of simple attacks that all happen to be coming from different vectors simultaneously" rather than a single multi-vector attack.
The application security firm concludes that the attack looks much more like an opportunistic assault than a targeted attack. VeraCode's analysis can be found in a blog post here. ®