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Category: Malware

Type: Trojan

Platform: SymbOS


Also known as a trojan horse program, this is a deceptive program that performs additional actions without the user's knowledge or permission.


If found, remove the following from the application manager:

  • Symbian S60 AknMime Services
  • Symbian S60 System InsSrv
  • Symbian S60 System UpdateSrv
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Technical Details

Trojan:SymbOS/MerogoSMS refers to a series of SMS worms that has been found spreading on Symbian Series 60 3rd Edition and Symbian Series 60 5th Edition devices. The worm spreads as self-signed (untrusted) SIS installers, which contain sub-SIS installers some of them signed by Symbian. All the related publisher IDs and certificates have been added to revocation list by Symbian.

This malware is discussed in our Lab Weblog:


The worm spreads by sending text messages that contain variable messages in Chinese and a link to a website at If the link is followed, an application will be installed promptly.


The malware will be registered to start on the phone boot up, and tries to connect to a website at http://rec[...]rzwxdsu.com over GPRS or 3G connection, infecting the phone and restarting the SMS spreading.

The worm has also been spread on different Chinese file sharing web sites in a file disguised as a game or theme for Symbian Series60 3rd & 5th edition phones.


No report on this malware has been received outside of China.