BKDR_PUSHDO
Pandex, Harebot, Pushdo
Windows 2000, Windows XP, Windows Server 2003
![](/vinfo/imgFiles/legend.jpg)
Threat Type: Backdoor
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
In 2009, Trend Micro researchers studied the relationship between the Pushdo botnet and CUTWAIL malware. It appeared that CUTWAIL is one of the malware downloaded by Pushdo and is used by the botnet mainly for spamming. Later on, the Pushdo botnet was also referred to as the Cutwail botnet.
In the botnet business model, CUTWAIL is one of the main starters of infections of ZEUS, and later on, FAKEAV. When a system is infected by CUTWAIL malware, it usually downloads a ZEUS or FAKEAV malware on the affected system as well.
Apart from its downloading routine, CUTWAIL is also known to perform distributed denial of service (DDoS) attacks against various sites. Sites that have been attacked by CUTWAIL are affiliated with various government agencies in differing countries. It also attacked several commercial sites.
TECHNICAL DETAILS
Installation
This backdoor drops the following copies of itself into the affected system:
- %System%\imPlayok.exe
- %System%\pmpviotnY.exe
- %System%\reader_s.exe
- %System%\reader_s.exe
- %System%\wuaucldt.exe
- %User Profile%\imPlayok.exe
- %User Profile%\pmpviotnY.exe
- %User Profile%\reader_s.exe
- %User Profile%\wuaucldt.exe
(Note: %System% is the Windows system folder, which is usually C:\Windows\System32.. %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.)
Autostart Technique
This backdoor adds the following registry entries to enable its automatic execution at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
syncman = "%User Profile%\wuaucldt.exe"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
syncman = "%System%\wuaucldt.exe"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
reader_s = "%User Profile%\reader_s.exe"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
reader_s = "%System%\reader_s.exe"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
pmpviotnY = "%User Profile%\pmpviotnY.exe"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
pmpviotnY = "%System%\pmpviotnY.exe"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
imPlayok = "%User Profile%\imPlayok.exe"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
imPlayok = "%System%\imPlayok.exe"
Other Details
This backdoor connects to the following possibly malicious URL:
- {BLOCKED}.{BLOCKED}.76.194
- {BLOCKED}.{BLOCKED}.62.66
- {BLOCKED}.{BLOCKED}.220.203
- {BLOCKED}.{BLOCKED}.187.4
- black.{BLOCKED}antom.com
- {BLOCKED}ash.com