Win32/FakeSpypro

Win32/FakeSpypro has been distributed with many different names. The user interface and other details vary to reflect each variant's individual branding. These different distributions of the rogue use various installation methods, with file names and system modifications that can differ from one variant to the next.

FakeSpypro distributions affecting users in the wild:

• Antispyware Soft

Installation

Win32/FakeSpypro may be installed from the program's web site or by social engineering from third-party web sites. When run, Win32/FakeSpypro copies itself to %windir%\sysguard.exe and sets a registry entry to run itself at each system start:

Adds value: "system tool"
With data: "%windir%\sysguard.exe"
To subkey: HKCU\Software\Microsoft\Windows\CurrentVersion\Run

It drops a DLL component to "<system folder>\iehelper.dll" and sets the following registry values to load the dropped DLL at Windows start and to register the DLL component as a browser helper object or plug-in:

Adds value: "(default)"
With data: "bho"
To subkey: HKLM\SOFTWARE\Classes\CLSID\{C9C42510-9B21-41c1-9DCD-8382A2D07C61}

Adds value: "(default)"
With data: "<system folder>\iehelper.dll"
To subkey: HKLM\SOFTWARE\Classes\CLSID\{C9C42510-9B21-41c1-9DCD-8382A2D07C61}\InProcServer32

Adds value: "(default)"
With data: "0"
To subkey: HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Browser Helper Objects\{C9C42510-9B21-41c1-9DCD-8382A2D07C61}

It also creates the following registry subkeys:

• HKCU\Software\AvScan
• HKCU\Software\AVSuite

Payload

Downloads files

Win32/FakeSpypro may download files from a particular URL. In the wild, it was observed downloading files from the spywrprotect-2009.com domain. 

Displays misleading messages and alerts

When the trojan's executable, sysguard.exe, runs it displays the following interface:

The trojan regularly displays false warnings of malware infection:

It can also display pop-ups such as the following:

Moderates Internet use

The DLL <system folder>\iehelper.dll installed by Win32/FakeSpypro is used to observe your Internet usage. For example, it may modify search results for the following search engines, by appearing to direct you to browser-security.microsoft.com:

• yahoo.com
• google
• msn.com
• live.com

The site, browser-security.microsoft.com, pretends to belong to Microsoft, however, it is used to distribute rogue security software. The site can appear similar to the following example:

The purpose of the message is to lure you to a page where you can purchase the rogue security product, such as the following:

Modifies hosts file

Win32/FakeSpypro modifies the Windows Hosts file. The local Hosts file overrides the DNS resolution of a web site URL to a particular IP address. Malicious software may make modifications to the Hosts file in order to redirect specified URLs to different IP addresses. Malware often modifies an affected machine's hosts file in order to stop users from accessing websites associated with particular security-related applications (such as antivirus software). 

Win32/FakeSpypro may modify the Hosts file under <system folder>\drivers\etc\hosts, to ensure that users visiting browser-security.microsoft.com are directed to the listed IP address as in the following example:

195.245.119.131 browser-security.microsoft.com

Blocks web browsing

Win32/FakeSpypro modifies the registry so that the trojan runs as its own proxy server to manage Internet browsing.

Adds value: "ProxyServer"
With data: "http=127.0.0.1:5555"
To subkey: HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings

The trojan lets you use a web browser, but any attempts to visit websites result in the display of a false "Internet Explorer Warning" message such as the following:

Analysis by Wei Li