Trojan:SymbOS/MapUP refers to a family of SMS-worms that spread on Symbian Series 60 3rd Edition and Symbian Series 60 5th Edition devices. It has no malicious payload, other than spreading itself.
Trojan:SymbOS/MapUp can be manually uninstalled by removing the following from the Application Manager:
- Update Package
- Ovi Store Installer
- Ovi Update
In addition to spreading via malicious SMS messages, MapUp has also been found hosted on file-sharing websites,, disguised as an update package or theme.
An unusual feature of this malware is that its malicious executable file is a Symbian-signed SIS installer, containing sub-SIS installers that are also signed. All relevant publisher IDs and certificates have been added to revocation list by Symbian.
At the time of publishing, no reports of this malware have been received outside of China.
The worm is distributed using an SMS message containing a (varying) text message in Chinese and a link to a website. If the link is followed, an application will be installed promptly.
The worm has also been found hosted on various Chinese file-sharing websites in a file disguised as a Nokia update package or theme for Symbian Series60 3rd & 5th edition phones.
During installation, the MapUP trojan registers itself to start on the phone boot up. Once active on restart, the trojan attempts to connect to a website via a GPRS or 3G connection, infecting the phone and restarting the SMS spreading.
The trojan also clears the user's communication logs to hide its actions.