Mobile phones users are receiving SMS text messages thanking them for subscribing to a fictitious dating service.  The message states that there is a subscription fee of $2.00 per day and it will be added to their phone bill unless the mobile phone user goes to a designated website to cancel their subscription.

Once the mobile phone user visits the site to unsubscribe, they are prompted to click on a link which downloads a Trojan horse program.  Once installed, the program that opens a back door on a compromised computer and blocks access to security-related Web sites. It also runs a keylogger, periodically sending the stolen information to a remote attacker.

Symantec's name for the Trojan horse is Nibu, but is also known as Dumador and CCT.  Systems affected are Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows XP