Trojan:SymbOS/Skulls.S

Classification

Category :

Malware

Type :

Trojan

Platform :

SymbOS

Aliases :

Skulls.S, SymbOS/Skulls.S

Summary

Skulls.S is a variant of SymbOS/Skulls.C trojan. The component files of the trojan are almost identical to Skulls.C. The main difference is that Skulls.S drops Cabir.F several times into the same device.

If Skulls.S is installed only the calling from the phone and answering calls works. All functions which need some system application, such as SMS and MMS messaging, web browsing and camera no longer function.

Removal

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 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.

Technical Details

Installation to system

Like Skulls.A Skulls.S is a SIS file that installs critical System ROM binaries and Cabir.F and Cabir.G worms into C: drive. The System ROM files are installed with exact same names and locations as in the ROM drive.

Symbian operating system has a feature which causes any file that is in C: drive replace file in ROM drive with identical name and location.

Spreading in: Liveupdate wireless.sis

Payload

Replaces built in applications with non-functional ones and installs Cabir.F worm.