Trojan:SymbOS/Flocker

Classification

Malware

Trojan

SymbOS

Trojan:SymbOS/Flocker, Trojan:SymbOS/Flocker

Summary

Trojan:SymbOS/Flocker.A is malware affecting Symbian S60 2nd Edition phones that are running an implementation of Python.

Removal

  • Reboot the phone
  • Start up the infected phone and the application installer should now work
  • Go to the application manager and uninstall the SIS file in which you installed the malware
  • Download F-Secure Mobile Security and activate it
  • Scan the phone and remove any remaining components of the malware

Suspect a file is incorrectly detected (a False Positive)?

A False Positive is when a file is incorrectly detected as harmful, usually because its code or behavior resembles known harmful programs. A False Positive will usually be fixed in a subsequent database update without any action needed on your part. If you wish, you may also:

  • Check for the latest database updates

    First check if your F-Secure security program is using the latest detection database updates, then try scanning the file again.

  • Submit a sample

    After checking, if you still believe the file is incorrectly detected, you can submit a sample of it for re-analysis.

    NOTE If the file was moved to quarantine, you need to collect the file from quarantine before you can submit it.

  • Exclude a file from further scanning

    If you are certain that the file is safe and want to continue using it, you can exclude it from further scanning by the F-Secure security product.

    Note You need administrative rights to change the settings.

Find out more

Knowledge Base

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User Guide

See the user guide for your product on the Help Center.

Contact Support

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Submit a sample

Submit a file or URL for further analysis.

Technical Details

Flocker.A is distributed in the form a SIS archive embedding a Python (programming language) script file, and as such, can effectively only run on S60 phones that have the Python environment installed. The Flocker.A SIS archive is complied for S60 2nd Edition and fails to install on 3rd Edition phones.

This trojan claims to be an ICQ (instant messaging) application in its attempt to trick the user.

The installation file is named "Icq_Python". After installation, an icon can be found in the phone's menu as if it were a legitimate application.

Flocker.A does not provide a functioning ICQ client.

When starting the application from the menu, Flocker.A starts continuously sending SMS messages to a hard coded phone number.

It deletes SMS messages from the Inbox whenever the messages are from the same number, probably in an attempt to mask the premium service reply to the infected phone.

Flocker.A attempts to send SMS messages to the number "3649" with a subject of "FILES 545".

Messages are sent in one second intervals and in the case of a failure the following message is shown to the user:

  • Message sending failed

User interaction is needed to close the message. This makes the phone unusable if the SMS fails to as a steady stream of error prompts will overwhelm the phone. A very large phone bill is highly probable should the messages successfully send.

System Installation

The following files are installed to the phone:

  • !:\balbes\???????.jpg
  • !:\system\apps\Icq_reggerNEW\default.py
  • !:\system\apps\Icq_reggerNEW\Icq_reggerNEW.app
  • !:\system\apps\Icq_reggerNEW\Icq_reggerNEW.rsc
  • !:\system\libs\appswitch.pyd
  • !:\system\libs\inbox.pyd
  • !:\system\libs\keypress.pyd