Updated The second worm to infect jailbroken iPhone users reportedly targets customers of Dutch online bank ING Direct.
Surfers visiting the site with infected devices are redirected to a phishing site designed to harvest online banking login details, the BBC reports. ING Direct told the BBC it planned to warn users' of the attack via its website, as well as briefing front line call centre staff on the threat.
Mikko Hypponen, chief research officer at F-Secure, said the threat had in any case been neutralised. "It [the worm] was targeting ING. The websites it needed for this to work have now been taken down."
Anti-virus analysts, still in the process of analysing the malware, caution that the attack is a bit more complex than simple phishing and seems to involve an attempt to snatch SMS messages associated with online banking transactions. We're yet to hear back from ING Direct on this point but we'll update this story as and when we hear more.
What is clear is that the "Duh" or Ikee-B worm, like the earlier Rickrolling worm, exploits an SSH backdoor on jailbroken handsets in order to spread.
Part of the process of jailbreaking iPhones to allow unofficial software to be installed can involve installing SSH (secure shell) remote access. Users who go through this step but fail to change the default root password of iPhones from alpine leave a backdoor that wide open to attack.
Although Duh exploits the same SSH backdoor as the original Ikee worm, the latest malware is far more dangerous than its predecessor. Doh turns compromised devices into a botnet under the control of unidentified hackers. The Rickrolling ikee worm, by contrast, only changes users' wallpaper to an image of cheesy pop warbler Rick Astley.
Duh also searches across a wider range of IP ranges than Ikee, which only ever affected Optus users in Australia. It includes IP ranges allocated to carriers in several countries, including The Netherlands, Portugal, Australia, Austria, and Hungary. All the infections reported thus far have happened in The Netherlands. The attack only came to light after a Dutch ISP noticed unusual traffic and began to investigate.
As previously reported, compromised phones are left under the control of a botnet server in Lithuania. Duh changes the root password of compromised iPhones, allowing crooks to log into compromised units and carry out malicious further actions.
SophosLabs researcher Paul Ducklin used a password cracking tool to discover the malware changes iPhone root passwords from 'alpine to 'ohshit'.
In addition to the two iPhone worms, an earlier hacking/extortion attack (targeting iPhone users in the Netherlands) also exploited the default password SSH backdoor on jailbroken iPhones.
Security experts strongly advise users of jailbroken phones to change their passwords from 'alpine' immediately to avoid further attacks along the same lines. ®