TROJ_SMALL_0000092.TOMA

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:

• %Windows%\Tasks\conime.exe

(Note: %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.)

It creates the following folders:

• %User Profile%\Microsoft\Dr Watson

(Note: %User Profile% is the current user's profile folder, which is usually C:\Windows\Profiles\{user name} on Windows 98 and ME, C:\WINNT\Profiles\{user name} on Windows NT, and C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003.)

Autostart Technique

This Trojan modifies the following registry entries to ensure it automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Winlogon
Userinit = "%System%\userinit.exe,%Windows%\Tasks\conime.exe"

(Note: The default value data of the said registry entry is %System%\userinit.exe,.)

Other System Modifications

This Trojan deletes the following files:

• %Windows%\Tasks\conime.exe
• %System Root%\boot

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

It deletes the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
PCHealth\ErrorReporting\DW

Dropping Routine

This Trojan drops the following files:

• %User Profile%\Dr Watson\drwtsn32.log

(Note: %User Profile% is the current user's profile folder, which is usually C:\Windows\Profiles\{user name} on Windows 98 and ME, C:\WINNT\Profiles\{user name} on Windows NT, and C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003.)

Other Details

This Trojan connects to the following possibly malicious URL:

• http://www.{BLOCKED}0.com/8888.txt

This report is generated via an automated analysis system.