Trojan.Win32.Qhost.vls

Technical Details
Payload
Removal instructions

Technical Details

A trojan program that carries out destructive actions on the user's computer. It is a Windows application (PE-EXE file). 6656 bytes. Written in C++.

Payload

The trojan is launched with a string parameter containing a pathway to a certain file. If launching without this parameter, the trojan shuts down without carrying out any actions.

When running, the trojan replaces the "hosts" file:

%System%\drivers\etc\hosts

with a file with a path obtained in the launch parameter. This means that the user may be redirected to certain sites or prevented from accessing certain resources. "Hidden" and "read only" attributes are then established for the "hosts" file. The trojan then deletes the file, the path to which is obtained from the launch parameter, and then shuts down.

Removal instructions

If your computer has not been protected with anti-virus software and has been infected with malware, you will need to take the following actions to delete this:

1. Delete the original trojan file (its location on the infected computer will depend on how the program got onto the computer).
2. Restore the original "hosts" file content:

   %System%\drivers\etc\hosts

   By default this is the following type of file:

   # (C) Microsoft Corp., 1993-1999
   #
   # It is a sample HOSTS file used by Microsoft TCP/IP for Windows.
   #
   # This file contains the mappings for the IP-addresses to the host names.
   # Each element should be located within a separate string. The IP-address should
   # be located in the first column, followed by the relevant name.
   # The IP-address and name of the host should be separated by at least one space.
   #
   # Moreover, some strings may contain comments
   # (details of the string). These should follow the name of the host and should be separated
   # from it by the '#' symbol.
   #
   # For example:
   #
   # 102.54.94.97 rhino.acme.com # source server
   # 38.25.63.10 x.acme.com # client host x
   
   127.0.0.1 localhost
   

3. Run a full Kaspersky Antivirus scan of the computer with updated antivirus databases (download trial version).

MD5: C97C8022899EBDB959A09630407D350E
SHA1: 90E48846988EB5D058D9B7A9D65AC2929662676D