Threat Descriptions

Trojan-Spy:W32/Zbot.GO

Classification

Category :

Malware

Type :

Trojan-Spy

Platform :

W32

Aliases :

Trojan-Spy:W32/Zbot.GO

Summary

Trojan-Spy:W32/Zbot.GO is a trojan that attempts to steal online banking login-information and other sensitive data from the infected computer.

Removal

Based on the settings of your F-Secure security product, it will either move the file to the quarantine where it cannot spread or cause harm, or remove it.

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

Trojan-Spy:W32/Zbot.GO copies itself to the following location:

  • %windir%\system32\ntos.exe

%windir% represents the system's default Windows directory.Zbot.GO appends a random amount of junk data to the copy in an attempt to make its detection more difficult.The trojan adds the following registry entry:

  • HKLM\software\microsoft\windows nt\currentversion \winlogon userinit = C:\WINDOWS\system32\userinit.exe, C:\WINDOWS\system32\ntos.exe

This entry ensures that the malware is executed every time the infected computer is started. When the trojan is executed it injects malicious code to other processes. The injected code starts listening for incoming TCP connections on three different ports and downloads the following data file:

  • 81.222.[Removed]/2/cfg.bin

Stealing banking information is the primary payload of Trojan-Spy:W32/Zbot.GO.It targets the following two sites by default:

  • onlineeast.bankofamerica.com
  • www.cajamar.es

Other targets can be added through the cfg.bin file that the trojan downloads.Login information is stolen when the victim visits a targeted website. The trojan also steals sensitive information such as passwords from the Windows Protected Storage and is able to take screenshots of the victim's desktop.Trojan-Spy:W32/Zbot.GO checks the running programs for firewall related processes:

  • outpost.exe
  • zlclient.exe

If either of them is running the trojan only copies itself under the system32 folder and creates the above mentioned registry key.