BEIJING, November 9 (Xinhuanet) -- Owners of "jail-broken" Apple i-Phones are at risk from a self-propogating worm, reports on Monday said. it is the first worm to infect the Apple i-Phone and has been discovered spreading "in the wild" across Australia. The program changes the phone's wallpaper to a picture of 1980s sing Rick Astley with a message "ikee is never going to give you up".

    The picture of Rick Astley is believed to be a reference to the internet phenomenon known as Rickrolling, where Internet users are tricked into clicking what they believe is a relevant link, only to find that it actually takes the user to a video of the pop star's song "Never gonna give you up".

    Only "jail-broken" have been affected according to reports. "Jail-breaking" is a process whereby a user removes Apple's protection mechanisms in order to allow the use of non-Apple compliant software. However, by doing so it has left some users open to such attacks. Up to 10 percent of all i-Phones and i-Pod Touch devices are believed to have been tampered in this way.

    While this particular worm is not harmful, albeit annoying, other more malicious worms may follow. "The creator of the worm has released full source code of the four existing variants of this worm," Mikko Hypponen of security firm F-secure writes. "This means that there will quickly be more variants, and they might have a nastier payload than just changing your wallpaper."

    The hacker, 21-year-old Ashley Towns, said he made the program to raise the issue of security. The worm can be removed by changing the phone's password and deleting some files. Graham Cluley from the security firm Sophos said it was important to change the default password in the devices. "What's clear is that if you have jail-broken your i-Phone or i-Pod Touch, and installed SSH, then you must always change your root user password to something different than the default, 'alpine'," he said.

    (Agencies)