System changes

The following system changes may indicate the presence of this malware:

• The presence of the following files:
  
  cleansweep.exe
  windowseep.exe
  collectors.txt
  webinjects.txt
  
  
• The presence of the following registry modifications:
  
  

  In subkey: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings
  Sets value: "EnableHttp1_1"
  With data: "1"

  In subkey: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\0
  Sets value: "1409"
  With data: "3"

  In subkey: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\1
  Sets value: "1409"
  With data: "3"

  In subkey: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\2
  Sets value: "1409"
  With data: "3"

  In subkey: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\3
  Sets value: "1409"
  With data: "3"

  In subkey: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\4
  Sets value: "1409"
  With data: "3"

  In subkey: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Lockdown_Zones\1
  Sets value: "1406"
  With data: "0"

  In subkey: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Lockdown_Zones\2
  Sets value: "1406"
  With data: "0"

  In subkey: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Lockdown_Zones\3
  Sets value: "1406"
  With data: "0"

  In subkey: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Lockdown_Zones\4
  Sets value: "1406"
  With data: "0"

  In subkey: HKCU\Software\Microsoft\Internet Explorer\PhishingFilter
  Sets value: "EnabledV8"
  With data: "0"

  In subkey: HKCU\Software\Microsoft\Internet Explorer\Recovery
  Sets value: "ClearBrowsingHistoryOnExit"
  With data: "0"

Installation

This malware may be installed by TrojanDropper:Win32/EyeStye. When run, the trojan creates one of the following mutex names to ensure only one instance of the malware executes:

• __SPYNET__
• __CLEANSWEEP__

Recent variants have also been observed creating mutexes with a configurable, variable name.

In the wild, we have observed the trojan dropping files in the directory in which it is executed. It may create a hidden top-level directory, using the following format:

• \<file name>\<file name>.exe

Where <file name> may be, but is not limited to, the following:

• cleansweep.exe
• windowseep.exe

For example, cleansweep\cleansweep.exe.

The registry is modified to run the malware at each Windows start.

In subkey: HKCU\Software\Microsoft\Windows\CurrentVersion\Run
Sets value: "<Win32/EyeStye file name>" (for example "syscheckrt.exe")
With data: "<path and file name of Win32/EyeStye>" (for example "c:\syscheckrt\syscheckrt.exe")

or

In subkey: HKCU\Software\Microsoft\Windows\CurrentVersion\Run
Sets value: "<random key>"
With data: "<path and file name of Win32/EyeStye>" (for example "c:\syscheckrt\syscheckrt.exe")

The configuration data file may also contain various "plug-ins" that are utilized to make up the malware's payload. This may include, the following:

• Backdoor functionality (either through RDP or a Socks5 proxy) allowing unauthorized access and control of the affected computer
• Jabber notification to the malware author of new infections
• Specific connections to use for transmission of stolen information to a remote attacker
• The ability to grab certificates from Firefox
• FTP functionality

The configuration file may contain the following files:

• config.dat
• screenshots.txt
• dns.txt
• <plug-in>.dll
• <plug-in>.cfg

Win32/EyeStye injects its payload into all currently running processes, while avoiding the following processes:

• smss.exe
• csrss.exe
• services.exe
• System
• <Win32/EyeStye process>

Payload

Lowers browser security zone settings

The malware modifies registry data that lowers browser security for Internet Explorer:

In subkey: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings
Sets value: "EnableHttp1_1"
With data: "1"

In subkey: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\0
Sets value: "1409"
With data: "3"

In subkey: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\1
Sets value: "1409"
With data: "3"

In subkey: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\2
Sets value: "1409"
With data: "3"

In subkey: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\3
Sets value: "1409"
With data: "3"

In subkey: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\4
Sets value: "1409"
With data: "3"

In subkey: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Lockdown_Zones\1
Sets value: "1406"
With data: "0"

In subkey: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Lockdown_Zones\2
Sets value: "1406"
With data: "0"

In subkey: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Lockdown_Zones\3
Sets value: "1406"
With data: "0"

In subkey: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Lockdown_Zones\4
Sets value: "1406"
With data: "0"

In subkey: HKCU\Software\Microsoft\Internet Explorer\PhishingFilter
Sets value: "EnabledV8"
With data: "0"

In subkey: HKCU\Software\Microsoft\Internet Explorer\Recovery
Sets value: "ClearBrowsingHistoryOnExit"
With data: "0"

Modifies Mozilla Firefox settings

• Disables safe browsing
• Disables malware blacklist check for downloads
• Disables alerts
• Disables clearing cookies and sessions

Uses stealth

Win32/EyeStye hooks the following APIs to prevent affected users from seeing malware files or system modifications with Windows Explorer, within a command prompt, or within the registry:

• NtEnumerateValueKey
• ZwEnumerateValueKey
• NtQueryDirectoryFile
• ZwQueryDirectoryFile
• NtVdmControl
• ZwVdmControl

Exports imported certificates

Captures sensitive information

Win32/EyeStye hooks the following Windows APIs to steal authentication information and alter web content presented to the user:

• HttpAddRequestHeadersA
• HttpOpenRequestA
• HttpSendRequestW
• HttpQueryInfoA
• InternetQueryDataAvailable
• InternetReadFile
• InternetReadFileExA
• InternetCloseHandle
• InternetQueryOptionA
• InternetWriteFile

The following Firefox APIs are also hooked for the same purpose:

• PR_Read
• PR_Write
• PR_Close
• PR_OpenTCPSocket
• PR_GetSocketOption
• PR_SetSocketOption
• PR_GetError
• PR_SetError

It hooks the following APIs to take screenshots of the affected computer:

• GdipSaveImageToStream
• GdipSaveImageToFile
• GdipCreateBitmapFromHBITMAP
• GdiplusShutdown
• GdiplusStartup

Bypasses SSL

Win32/EyeStye hooks the API "CryptEncrypt" to intercept SSL traffic. If the security program Trusteer Rapport is running, the malware returns an error "NTE_NO_MEMORY" so that plain authentication is used.

Sends captured data to a remote server

The trojan attempts to send captured data via HTTP post to a remote server. In the wild, we have observed this trojan connecting to the following remote servers:

• microsoft-windows-security.com (not a Microsoft.com domain)
• vinodelam.net
• overclock.osa.pl
• qualitaetvorun.org
• svetodioduk.net
• rtjhteyjtyjtyj.orge.pl
• airiston.net
• superboy999.ru
• vertime.ru
• bettasbreed.co.cc
• nusofttechnologies.info
• svetodioduk2.com
• fieldsoflove.cc
• fightforce.cc
• totalhidden.cc
• feldmar.ru
• lyambosok.ru
• picomarkets.ru
• primedyl.com
• domain391.org
• securegateonline.com
• reg.kygalu.ru
• domain191.org
• black-hosting.ru
• hfhfhfhfee.com

It has been observed contacting the following remote server:

traxbax.<removed>/user/gate<removed>

While sending captured data, it may include the following additional information:

• "Bot guid" - unique identifier associated with the trojan
• User name
• Computer name
• Volume serial number
• Process name associated with captured data
• Name of hooked API function (for example PR_Write)
• Captured raw data
• Keys, logged keystrokes
• Other information specific to computer locale such as:
• Local time
• Time zone
• Operating system version
• Language

Take the following steps to help prevent infection on your computer:

• Enable a firewall on your computer.
• Get the latest computer updates for all your installed software.
• Use up-to-date antivirus software.
• Limit user privileges on the computer.
• Use caution when opening attachments and accepting file transfers.
• Use caution when clicking on links to webpages.
• Avoid downloading pirated software.
• Protect yourself against social engineering attacks.
• Use strong passwords.

Enable a firewall on your computer

Use a third-party firewall product or turn on the Microsoft Windows Internet Connection Firewall.

• How to turn on the Windows Firewall in Windows 7
• How to turn on the Windows Firewall in Windows Vista
• How to turn on the Windows firewall in Windows XP

Get the latest computer updates

Updates help protect your computer from viruses, worms, and other threats as they are discovered. It is important to install updates for all the software that is installed in your computer. These are usually available from vendor websites. Instructions on how to download the latest versions of some common software is available from the following:

• Microsoft Malware Protection Center - Updating Software

You can use the Automatic Updates feature in Windows to automatically download future Microsoft security updates while your computer is on and connected to the Internet.

• How to turn on Automatic Updates in Windows 7
• How to turn on Automatic Updates in Windows Vista
• How to turn on Automatic Updates in Windows XP

Use up-to-date antivirus software

Most antivirus software can detect and prevent infection by known malicious software. To help protect you from infection, you should always run antivirus software, such as Microsoft Security Essentials, that is updated with the latest signature files. For more information, see http://www.microsoft.com/windows/antivirus-partners/.

Limit user privileges on the computer

Starting with Windows Vista and Windows 7, Microsoft introduced User Account Control (UAC), which, when enabled, allowed users to run with least user privileges. This scenario limits the possibility of attacks by malware and other threats that require administrative privileges to run.

You can configure UAC in your computer to meet your preferences:

• User Account Control in Windows 7
• User Account Control in Windows Vista
• Applying the Principle of Least Privilege in Windows XP
• More on User Account Control

Use caution when opening attachments and accepting file transfers

Exercise caution with email and attachments received from unknown sources, or received unexpectedly from known sources. Use extreme caution when accepting file transfers from known or unknown sources.

Use caution when clicking on links to webpages

Exercise caution with links to webpages that you receive from unknown sources, especially if the links are to a webpage that you are not familiar with, unsure of the destination of, or suspicious of. Malicious software may be installed in your computer simply by visiting a webpage with harmful content.

Avoid downloading pirated software

Threats may also be bundled with software and files that are available for download on various torrent sites. Downloading "cracked" or "pirated" software from these sites carries not only the risk of being infected with malware, but is also illegal. For more information, see 'The risks of obtaining and using pirated software'.

Protect yourself from social engineering attacks

While attackers may attempt to exploit vulnerabilities in hardware or software to compromise a computer, they also attempt to exploit vulnerabilities in human behavior to do the same. When an attacker attempts to take advantage of human behavior to persuade the affected user to perform an action of the attacker's choice, it is known as 'social engineering'. Essentially, social engineering is an attack against the human interface of the targeted computer. For more information, see 'What is social engineering?'.

Use strong passwords

Attackers may try to gain access to your Windows account by guessing your password. It is therefore important that you use a strong password – one that cannot be easily guessed by an attacker. A strong password is one that has at least eight characters, and combines letters, numbers, and symbols. For more information, see http://www.microsoft.com/protect/yourself/password/create.mspx.

To detect and remove this threat and other malicious software that may be installed on your computer, run a full-system scan with an appropriate, up-to-date, security solution. The following Microsoft products detect and remove this threat:

• Microsoft Security Essentials
• Microsoft Safety Scanner
• Windows Defender
• Microsoft Windows Malicious Software Removal Tool

For more information on antivirus software, see http://www.microsoft.com/windows/antivirus-partners/.