BKDR_PLUGX.GEL

This backdoor arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It does not have any propagation routine.

It executes commands from a remote malicious user, effectively compromising the affected system.

It executes the dropped file(s). As a result, malicious routines of the dropped files are exhibited on the affected system.

It does not have any downloading capability.

It deletes the initially executed copy of itself.

Arrival Details

This backdoor arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This backdoor creates the following folders:

• %All Users Profile%\DRM\EPWING

(Note: %All Users Profile% is the All Users or Common profile folder, which is C:\Documents and Settings\All Users in Windows 2000, XP, and Server 2003, and C:\ProgramData in Windows Vista and 7.)

It adds the following mutexes to ensure that only one of its copies runs at any one time:

• Global\{random}

It stays memory-resident by injecting codes into the following processes:

• svchost.exe
• msiexec.exe

Autostart Technique

This backdoor registers itself as a system service to ensure its automatic execution at every system startup by adding the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\EPWING
ImagePath = "%All Users Profile%\DRM\EPWING\mcupdui.exe"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\EPWING
DisplayName = "EPWING"

Other System Modifications

This backdoor adds the following registry keys:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Setttings\
5.0\User Agent

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Setttings\
5.0\User Agent\Post Platform

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Setttings\
User Agent

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Setttings\
User Agent\Post Platform

It modifies the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings
ProxyEnable = "0"

(Note: The default value data of the said registry entry is "1".)

Propagation

This backdoor does not have any propagation routine.

Backdoor Routine

This backdoor executes the following commands from a remote malicious user:

• Copy, move, rename, delete files
• Create directories
• Create files
• Enumerate files
• Execute files
• Get drive information
• Get file information
• Open and modify files
• Log keystrokes and active window
• Enumerate TCP and UDP connections
• Enumerate network resources
• Set TCP connection state
• Lock workstation
• Log off user
• Restart/Reboot/Shutdown system
• Display a message box
• Perfrom port mapping
• Enumerate processes
• Get process information
• Terminate processes
• Enumerate registry keys
• Create registry keys
• Delete registry keys
• Copy registry keys
• Enumerate registry entries
• Modify registry entries
• Delete registry values
• Screen capture
• Delete services
• Enumerate services
• Get service information
• Modify services
• Start services
• Perform remote shell
• Host Telnet server
• Connect to a database server and execute SQL statement

It connects to the following URL(s) to send and receive commands from a remote malicious user:

• http://{BLOCKED}ce.{BLOCKED}airgo.com:443/{hex values}

Dropping Routine

This backdoor drops the following files:

• %All Users Profile%\DRM\EPWING\mcupdui.exe - a legitimate McAfee (McAfee McUpdUI EXE)
• %All Users Profile%\DRM\EPWING\McUtil.dll - detected also as BKDR_PLUGX.GEL
• %All Users Profile%\DRM\EPWING\McUtil.dll.ping - detected also as BKDR_PLUGX.GEL
• %All Users Profile%\DRM\EPWING\{random}

(Note: %All Users Profile% is the All Users or Common profile folder, which is C:\Documents and Settings\All Users in Windows 2000, XP, and Server 2003, and C:\ProgramData in Windows Vista and 7.)

It executes the dropped file(s). As a result, malicious routines of the dropped files are exhibited on the affected system.

Download Routine

This backdoor does not have any downloading capability.

Other Details

This backdoor deletes the initially executed copy of itself

NOTES:

It terminates explorer.exe while doing this malicious routine

It does not have rootkit capabilities.

It does not exploit any vulnerability.