By Sia Ling Xin

SOME iPhone owners in Australia got a rude shock yesterday when they found their phones displaying a wallpaper of 1980s pop idol Rick Astley's photograph, emblazoned with a message: "Ikee is never going to give you up".

They were victims of the world's first iPhone virus, Ikee, which has infected phones there that were either "jailbroken" - had Apple's protective software removed - or did not have their default password, 'alpine', changed.

Once in place, the worm appeared to have found other iPhones on the mobile-phone network that were similarly vulnerable, and installed itself again.

IT-security and data-protection company Sophos' senior technology consultant, Mr Graham Cluley, said: "The first indication that anything is wrong with your iPhone is if you see a picture of Rick Astley.

"Fortunately, the worm doesn't do anything more malicious than that - it doesn't steal information, access your e-mail or snoop on your calls. But the source code has been made available on the Internet - meaning other hackers could create more dangerous versions of the worm."

Mr Paul Ducklin, Sophos' head of technology for the Asia-Pacific, said that phones are "jailbroken" so that they can run any software, and users can download applications that were previously unavailable through the official App Store, via unofficial installers such as Cydia. To protect their phones, users should change the default password, to one that is preferably not in the dictionary, he added.

In online reports, Cydia founder Jay Freeman estimates that four million out of 40 million iPods and iPhones have been jailbroken.

Home-grown telecommunications company SingTel has brought in more than 100,000 iPhones since it began selling them last August.

Singaporean iPhone user Joel Loh, 29, a bank executive, said: "It is worrying, but I suppose it's a lesson not to 'jailbreak', or make unauthorised changes to any device."

The hacker, 21-year-student Ashley Towns, told Australia's ABC News Online that he created the virus out of boredom, and to raise the issue of security.

So far, the worm has been confirmed to be circulating only in Australia, where he lives.

However, Mr Ducklin said: "There are also unconfirmed reports of Ikee in Thailand and Japan." The attack has resulted in a flood of users expressing their dismay on online forum discussions.

Ikee victim Alan Lee posted on an Australian forum: "How do you not know there is not something else happening, like monitoring what you do, the e-mail you read and websites you visit?"

The BBC said that the use of Rick Astley's photo and the reference to his song "Never gonna give you up" appear to be linked to an Internet phenomenon known as "Rickrolling".

That tricks Web users into clicking on what they believe to be a relevant link, only to see a video of the song.

The first known instance of "Rickrolling" occurred in May 2007.

When contacted on the incident yesterday, Apple declined to comment.

lingxin@sph.com.sg

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