System Security is a variant of Win32/Winwebsec - a family of programs that claims to scan for malware and displays fake warnings of “malicious programs and viruses”. They then inform the user that they need to pay money to register the software in order to remove these non-existent threats.
Win32/Winwebsec has been distributed with many different names. The name used by the malware, the user interface and other details vary to reflect each variant’s individual branding. The following details describe Win32/Winwebsec when it is distributed with the name System Security.
The installer downloads a ZIP file and installs files from the ZIP. In the wild, we have observed this file being downloaded with the filename 'ws.zip' from the 'securedownloadsoftware.com' domain. It displays the following image as it downloads,
and this image when it has finished installation:
It then runs the fake scanner.
It creates a directory under %COMMON_APPDATA% with a randomly generated name (e.g. C:\Documents and Settings\All Users\Application Data\922926319). The fake scanner is copied to this directory, also using a randomly generated file name (e.g. "1677291695.exe"). It also installs the following clean files:
The registry is modified to ensure that the fake scanner is executed at each Windows start:
Adds value: "<randomly generated>" (same as the fake scanner file name, e.g. 1677291695)
With data: "<path to rogue>" (e.g. C:\Documents and Settings\All Users\Application Data\922926319\1677291695.exe)
To subkey: HKLM\SOFTWARE\MICROSOFT\WINDOWS\CURRENTVERSION\RUN
It also creates the following shortcuts to the rogue executable on the desktop and in a new folder under Start | Programs:
Displays false/misleading malware alerts
When run, the malware performs a fake scan of the system, and falsely claims that a number of files on the system are infected with malware. Should users request that it clean the reported infections, it advises them that they need to pay money to register the program in order for it to do so.
See below for examples of the interface, fake alerts, false scanning results, icons and pop-ups used by Win32/Winwebsec when distributed as 'System Security':
Winwebsec may also display a dialog, similar to the following example, that appears to be closely modeled on the Windows Security Center: