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Win32/Virut.NBP

Aliases:Virus.Win32.Virut.ce (Kaspersky), W32/Virut.n.gen (McAfee), W32.Virut.CF (Symantec) 
Type of infiltration:Virus 
Size:Approximately 19 KB 
Affected platforms:Microsoft Windows 
Signature database version:4032 (20090424) 

Short description
Win32/Virut.NBP is a polymorphic file infector. The virus connects to the IRC network. It can be controlled remotely.
Executable file infection
The virus searches for executables with one of the following extensions:
  • .exe
  • .scr
Executables are infected by appending the code of the virus to the last section.

The host file is modified in a way that causes the virus to be executed prior to running the original code. The size of the inserted code is 19 KB .

It avoids those with any of the following strings in their names:
  • WINC
  • WCUN
  • WC32
  • OTSP
It infects the following files:
  • *.htm*
  • *.php*
  • *.asp*
The virus inserts a/an IFrame element with an URL link into the file.
Other information
The virus is sent data and commands from a remote computer or the Internet.

It communicates with the following servers using IRC protocol:
  • irc.zief.pl
  • proxim.ircgalaxy.pl
It can execute the following operations:
  • download files from a remote computer and/or Internet
  • run executable files
The following file is modified:
  • %system%\drivers\etc\hosts
The virus writes the following entries to the file:
  • 127.0.0.1 jL.chura.pl
The virus creates and runs a new thread with its own program code in all running processes.

The virus may set the following Registry entries:
  • [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\
    SharedAccess\Parameters\FirewallPolicy\StandardProfile\
    AuthorizedApplications\List]
    "%filepath%" = "%filepath%:*:enabled:@shell32.dll,-1"
The performed data entry creates an exception in the Windows Firewall program.