It seems like viruses for the iPhone are on the increase, following the discovery of a security hole by a Dutch hacker. A worm has popped up that appears to be infecting jailbroken handsets in Australia.

The Ikee worm doesn't do anything terribly malicious - it changes the handset's wallpaper to an image of Rick Astley and then attempts to find more handsets to infect. However, it could easily be modified to steal contact info or log keypresses, which would be of considerably more concern.

As previously reported on Pocket-lint, the hole only affects jailbroken iPhones that are running an SSH utility and haven't had the default password - "alpine" - changed. Usefully, this virus will disable the SSH application from running, preventing the handset from being infected any further.

Apple hasn't yet commented, but as this issue only affects jailbroken handsets, it's unlikely we'll be hearing much from the big fruit on this one. In the meantime, if you're running an unlocked iPhone, go change your password. Here's how to do it.