TROJ_KRYPTIK.XXYE

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It deletes itself after execution.

Arrival Details

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This Trojan drops and executes the following files:

• %Windows%\wmsa.exe - detected as BKDR_REMOSH.JC
• %User Temp%\selfkill.bat - batch file to delete the malware
• %System Root%\os.ipsec - contains IP security configuration (deleted after execution)
• %System Root%\netbois.sdb - database for system settings configuration (deleted after execution)

(Note: %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.. %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.)

It adds the following processes:

• cmd.exe /c net stop Windows32_Update
• cmd.exe /c taskkill /f /im update64.exe
• cmd.exe /c del /f /s /q c:\widnows\dell\svchost.exe
• cmd.exe /c del /f /s /q c:\widnows\dell\run.bat
• cmd.exe /c del /f /s /q c:\widnows\dell\update64.exe
• cmd.exe /c del /f /s /q c:\widnows\dell\run64.bat
• cmd.exe /c secedit /configure /db c:\netbois.sdb
• cmd /c %User Temp%\selfkill.bat /max
• cmd.exe /c netsh ipsec importpolicy %System Root%\os.ipsec
• cmd.exe /c netsh ipsec static set policy name=445 assign=y
• cmd.exe /c sc config wuauserv start=disabled
• cmd.exe /c net stop wuauserv
• cmd /c net user IUSR_ADMIN /del

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.)

Other Details

This Trojan deletes itself after execution.