TROJ_KRYPTK.YYKZ

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.

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 the following copies of itself into the affected system:

• %System%\{random filename 2}.exe
• %Application Data%\{random foldername}\{random filename}.exe

(Note: %System% is the Windows system folder, which is usually C:\Windows\System32.. %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)

It drops the following files:

• %Tasks%\Security Center Update - {number}.job

Autostart Technique

This Trojan adds the following registry entries to enable its automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
{random entry} = "%Application Data%\{random folder name}\{random filename}.exe"

HKEY_CURRENT_USER\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
{random entry} = "%Application Data%\{random folder name}\{random filename}.exe"

Other System Modifications

This Trojan adds the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\ELowcQ

HKEY_LOCAL_MACHINE\SOFTWARE\{random key}

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SecurityCenterServer{number}

HKEY_CURRENT_USER\Software\ELowcQ

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\{random key}
License = "444"

Other Details

This Trojan connects to the following possibly malicious URL:

• http://{BLOCKED}-vaper.su