BKDR_DEMTRANC

DEMTRANC is a typical botnet that targets Windows-based machines. It has downloading capabilities and remote shell command used to distribute other malware. Most samples arrive via exploited Flash file (.SWF) and .PDF files.

Installation

This backdoor drops the following files:

• %Application Data%\Microsoft\plugin_containor.exe
• %Application Data%\Help\iexplore.exe

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming 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
Plugin Container = "%Application Data%\Microsoft\plugin_containor.exe"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
iexplore = "%Application Data%\Help\iexplore.exe"

Other Details

This backdoor connects to the following possibly malicious URL:

• {BLOCKED}.{BLOCKED}.131.201/{3 Letter Header}{value}O{value}.jsp?{value}
• flying.{BLOCKED}1.us/{3 Letter Header}{value}O{value}.jsp?{value}
• kiki.{BLOCKED}S.biz/{3 Letter Header}{value}O{value}.jsp?{value}
• koranws.{BLOCKED}h.com/{3 Letter Header}{value}O{value}.jsp?{value}
• wwvv.{BLOCKED}dns.org.uk/{3 Letter Header}{value}O{value}.jsp?{value}