This trojan steals any information related to Brazilian
Internet banking websites. The trojan uses a legitimate
malware removal tool to maliciously remove some forms of
security software that some Brazilian Internet banking
websites require. The removal of the security software paves
the way to allow the trojan to steal a user's credentials; the
stolen credentials can then be forwarded to a remote server
for further malicious use.The trojan targets popular Brazilian
Internet banking websites, such as:
- https://www.bancobrasil.com.br/
- https://www.banrisul.com.br/
- https://www.bradesco.com.br/
- https://www.caixa.gov.br/
- https://www.citibank.com.br/
- https://www.credicardcitinovo.com.br/
- https://internetbanking.caixa.gov.br
- https://www.unibanco.com.br
- http://www.santanderbanespa.com.br/
The trojan will also attempt to download and execute files
from a remote server.
Execution
Upon execution, the trojan first drops a copy of itself as
It then downloads and executes the legitimate removal tool,
Avenger by Swandog. It also creates a number of files to
facilitate the smooth execution of its activity. For example,
%windir%\system32\drivers\workray.sys is a driver
file used by Avenger to operate normally.
Avenger will be executed in quiet mode, using the tool's
parameter, avenger.exe /nogui C:\systemX86.txt.
The legitimate files that will be removed by Avenger are
specified on the text file, C:\systemX86.txt. Of
particular interest is GbPlugin, a program used by Brazilian
banks to protect customers when they perform Internet banking
transactions. Though normally difficult to remove, using the
Avenger program allows the trojan to remove the GbPlugin at
the next system startup or reboot. The following is a typical
script used by Avenger to remove files:
Files to delete:
-
%systemdrive%\Arquivos de programas\GbPlugin\scpsssh2.dll
-
%systemdrive%\Arquivos de programas\GbPlugin\gbiehuni.dll
-
%systemdrive%\Arquivos de programas\GbPlugin\gbpdist.dll
- %systemdrive%\Arquivos de programas\GbPlugin\isg.gpc
- %systemdrive%\Arquivos de programas\GbPlugin\uni.gpc
-
%systemdrive%\Arquivos de programas\GbPlugin\gbiehisg.dll
-
%systemdrive%\Arquivos de programas\GbPlugin\GBIEHCEF.DLL
-
%systemdrive%\Arquivos de programas\GbPlugin\scpVista.exe
-
%systemdrive%\Arquivos de programas\GbPlugin\gbiehabn.dll
-
%systemdrive%\Arquivos de programas\GbPlugin\GBIEHABN.DLL
-
%systemdrive%\Arquivos de programas\GbPlugin\LOGOF.DLL
- %systemdrive%\Arquivos de programas\GbPlugin\abn.gpc
-
%systemdrive%\Arquivos de programas\GbPlugin\AtmCap.ocx
-
%systemdrive%\Arquivos de programas\GbPlugin\gbpsv.exe
-
%systemdrive%\Arquivos de programas\GbPlugin\GbpSv.exe
-
%systemdrive%\Arquivos de programas\GbPlugin\GbpSrv.exe
-
%systemdrive%\Arquivos de programas\GbPlugin\gbpsrv.exe
-
%systemdrive%\Arquivos de programas\GbPlugin\gbieh.dll
-
%systemdrive%\Arquivos de programas\GbPlugin\gbieh.dll
-
%systemdrive%\Arquivos de programas\GbPlugin\gbieh.gmd
- %systemdrive%\Arquivos de programas\GbPlugin\bb.gpc
- %systemdrive%\Arquivos de Programas\Scpad\scpMIB.dll
- %systemdrive%\program files\Scpad\scpsssh2.dll
- %systemdrive%\program files\Scpad\sshib.dll
- %systemdrive%\program files\Scpad\scpIBCfg.bin
- %systemdrive%\program files\Scpad\scpLIB.dll
- %systemdrive%\program files\scpsssh2.dll
- %systemdrive%\program files\gbiehuni.dll
- %systemdrive%\program files\gbpdist.dll
- %systemdrive%\program files\isg.gpc
- %systemdrive%\program files\uni.gpc
- %systemdrive%\program files\gbiehisg.dll
- %systemdrive%\program files\GBIEHCEF.DLL
- %systemdrive%\program files\gbiehabn.dll
- %systemdrive%\program files\GBIEHABN.DLL
- %systemdrive%\program files\LOGOF.DLL
- %systemdrive%\program files\abn.gpc
- %systemdrive%\program files\AtmCap.ocx
- %systemdrive%\program files\gbpsv.exe
- %systemdrive%\program files\GbpSv.exe
- %systemdrive%\program files\GbpSrv.exe
- %systemdrive%\program files\gbpsrv.exe
- %systemdrive%\program files\gbieh.dll
- %systemdrive%\program files\gbieh.gmd
- %systemdrive%\program files\bb.gpc
-
%systemdrive%\program files\GbPlugin\Scpad\scpsssh2.dll
- %systemdrive%\program files\GbPlugin\Scpad\sshib.dll
-
%systemdrive%\program files\GbPlugin\Scpad\scpIBCfg.bin
- %systemdrive%\program files\GbPlugin\Scpad\scpLIB.dll
- %systemdrive%\program files\GbPlugin\scpsssh2.dll
- %systemdrive%\program files\GbPlugin\gbiehuni.dll
- %systemdrive%\program files\GbPlugin\gbpdist.dll
- %systemdrive%\program files\GbPlugin\isg.gpc
- %systemdrive%\program files\GbPlugin\uni.gpc
- %systemdrive%\program files\GbPlugin\gbiehisg.dll
- %systemdrive%\program files\GbPlugin\GBIEHCEF.DLL
- %systemdrive%\program files\GbPlugin\gbiehabn.dll
- %systemdrive%\program files\GbPlugin\GBIEHABN.DLL
- %systemdrive%\program files\GbPlugin\LOGOF.DLL
- %systemdrive%\program files\GbPlugin\abn.gpc
- %systemdrive%\program files\GbPlugin\AtmCap.ocx
- %systemdrive%\program files\GbPlugin\gbpsv.exe
- %systemdrive%\program files\GbPlugin\GbpSv.exe
- %systemdrive%\program files\GbPlugin\GbpSrv.exe
- %systemdrive%\program files\GbPlugin\gbpsrv.exe
- %systemdrive%\program files\GbPlugin\gbieh.dll
- %systemdrive%\program files\GbPlugin\gbieh.gmd
- %systemdrive%\program files\GbPlugin\bb.gpc
- %windir%\scpVista.exe
- %windir%\gbpsv.exe
- %windir%\gbpsrv.exe
-
%systemdrive%\Arquivos de programas\GbPlugin\GbpSrv.exe
-
%systemdrive%\Arquivos de programas\GbPlugin\scpVista.exe
- %systemdrive%\avenger.txt
Folders to delete:
- %systemdrive%\program files\GbPlugin\
-
%systemdrive%\Arquivos de programas\GbPlugin\
%systemdrive%\program files\Scpad\ %systemdrive%\Arquivos de
programas\Scpad\
The script is stored on
%windir%\system32\awou.txt. After successfully
deleting the targeted files, the text file
C:\avenger.txtis created, containing the log of
the removal process. Finally, the cleanup script,
C:\cleanup.bat, will delete the backup files
created by Avenger.
Data Stealing
Once the security measures are removed, the trojan can proceed
to its data stealing routine. When the user browses a targeted
online banking website, the trojan is able to inject malicious
HTML into the webpage. The injection allows the trojan to
capture keystrokes the user enters into the log-in fields of
the website, essentially stealing the user's credentials.The
stolen credentials are then sent to a number of email
addresses registered under VFEmail and Inbox.com:
- h3llm45t[...]@vfemail.net
- h3llm45t[...]@vfemail.net
- jaodas[...]@inbox.com
File System Changes
Creates these files:
- %windir%\msnmsgsr.exe
- %windir%\system32\avenger.exe
- %windir%\system32\awou.txt
- %windir%\system32\Enviou2u2u.txt
- %windir%\system32\drivers\workray.sys
- %temp%\bloreg222a
- %temp%\blokil2a
- C:\Documents
-
Settings\All Users\Start Menu\Programs\Startup\avg.exe
- C:\cleanup.bat
- C:\cleanup.exe
- C:\systemX86.txt
- C:\zip.exe
Process Changes
Creates these processes:
- %windir%\system32\cmd.exe
- %windir%\system32\netsh.exe
Network Connections
Attempts to download files from:
- http://www.paeksan.com/technote/[...].jpg
Attempts to connect with HTTP to:
- http://www.natafeliz.my-webs.org/[...].php
Registry Modifications
Sets these values:
-
[HKLM\Software\Microsoft\Windows\CurrentVersion\Run] Msn =
C:\WINDOWS\msnmsgsr.exe
-
[HKLM\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile]
EnableFirewall = 00000000
Creates these keys:
- [HKLM\Software\Microsoft\Tracing\FWCFG ]