Trojan:SymbOS/Pbstealer.E

Classification

Category :

Malware

Type :

Trojan

Platform :

SymbOS

Aliases :

SymbOS/Pbstealer.E, Trojan:SymbOS/Pbstealer.E

Summary

Trojan:SymbOS/Pbstealer.E steals information from a phone (Contacts, Notepad, Calendar, etc) and attempts to forward the stolen data to a random Bluetooth-accessible phone within range.

Removal

F-Secure Mobile Anti-Virus is capable to detecting and deleting the Pbstealer.E trojan. Pbstealer.E tries to remove itself after sending data over Bluetooth. This self-removal doesn't always work, but fortunately it can be also removed by uninstalling it with Symbian application manager.

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

Payload

Pbstealer.E is distributed in a malicious SIS file that contains Pbstealer.E application file and string resource. When the SIS file is installed, Pbstealer.E starts automatically and shows the following text:

Compacting your contact(s), step2 Please wait againuntil done...

While showing the text, the Pbstealer.E reads all contacts information in the phone contact database, and copies the information to file C:\SYSTEM\MAIL\PHONEBOOK.TXT. In addition to contacts information, Pbstealer.E also copies the contents of Notepad and Calendar ToDo database files. But, this information is not very readable to receiver as the resulting file contains in the databases is in binary form. If the Notepad and Calendar are empty, it simply fails in execution. After building the text file, Pbstealer.E searches for the first device it finds over Bluetooth and sends the text file to it. When trying to send the file over Bluetooth, the Pbstealer.E uses repeated connection attempts, so that if user answers no, he will immediately get a second connection request. This technique is similar to the propagation tactic used by Cabir, except that Pbstealer will give up attempts after one minute and exit. If the user of the target phone accepts the Bluetooth transfer, he will receive a text file that contains information copied from the infected phones contacts database.

Note

Although Pbstealer.E uses Bluetooth for sending phone book data, this data is pure text and cannot infect the receiving device.