TROJ_KRYPTIK.LNY

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 connects to certain URLs. It may do this to remotely inform a malicious user of its installation. It may also do this to download possibly malicious files onto the computer, which puts the computer at a greater risk of infection by other threats. As of this writing, the said sites are inaccessible.

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 Root%\Documents and Settings\All Users\Local Settings\Temp\msdubmnax.exe

(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)

It adds the following processes:

• wuauclt.exe

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\policies\
Explorer\Run
55011 = "%System Root%\DOCUME~1\ALLUSE~1\LOCAL~1\Temp\msdubmnax.exe"

Download Routine

This Trojan connects to the following malicious URLs:

• {BLOCKED}f.ru

As of this writing, the said sites are inaccessible.

Other Details

This Trojan does the following:

• It injects codes into its created process, wuauclt.exe.