AntivirusBEST is a variant of Win32/FakeXPA - 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. Some members of the Win32/FakeXPA family may also download additional malware and have been observed in the wild downloading variants of Win32/Alureon
Win32/FakeXPA 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/FakeXPA when it is distributed with the name AntivirusBEST.
The following system changes may be made by Win32/FakeXPA when distributed as AntivirusBEST.
When installed, the following files are created:
The following modifications are made to the registry (for example):
Sets value: "AntivirusBEST"
With data: “%COMMON_APPDATA%\AB\Installer.exe”
To subkey: HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
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.
Please see below for examples of interface, fake alerts, false scanning results, and pop-ups used by Win32/FakeXPA when distributed as AntivirusBEST.