WORM_OSCARBOT.SLS

This worm arrives by connecting affected removable drives to a system. It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.

It runs certain commands that it receives remotely from a malicious user. Doing this puts the affected computer and information found on the computer at greater risk.

Arrival Details

This worm arrives by connecting affected removable drives to a system.

It 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 worm drops the following copies of itself into the affected system:

• %Application Data%\afd.exe

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

It drops the following file(s)/component(s):

• %User Temp%\rmme{4 numbers}.bat

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003.)

It adds the following mutexes to ensure that only one of its copies runs at any one time:

• stripp

It terminates itself if it finds the following processes in the affected system's memory:

• Wireshark
• tcpview
• filemon
• procmon

Autostart Technique

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Cftmon32 = "%Application Data%\afd.exe"

HKEY_CURRENT_USER\Software\Microsoft\
Windows NT\CurrentVersion\Terminal Server\
Install\Software\Microsoft\
Windows\CurrentVersion\Run
Cftmon32 = "%Application Data%\afd.exe"

Other System Modifications

This worm creates the following registry entry(ies) to bypass Windows Firewall:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
{malware path}\{malware name}.exe = "{malware path}\{malware name}.exe:*:Enabled:1"

Propagation

This worm creates the following folders in all removable drives:

• Folder
• Folder\SubFolder

It drops the following copy(ies) of itself in all removable drives:

• Folder\SubFolder\file.exe

It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.

The said .INF file contains the following strings:

;{garbage chracters}
[autorun
;{garbage chracters}
open=Folder\SubFolder\file.exe
icon=%SystemRoot%\system32\SHELL32.dll,4
action=Open folder to view files using Windows Explorer
shell\\open\command=Folder\SubFolder\file.exe
shell\\explore\command=Folder\SubFolder\file.exe
useautoplay=1

Backdoor Routine

This worm connects to any of the following IRC server(s):

• one.{BLOCKED}t.com

It joins any of the following IRC channel(s):

• #stdout

It executes the following command(s) from a remote malicious user:

• Download files
• Perform SYN floods
• Perform DDOS attacks
• Propagate via MSN, AIM
• Steal passwords from Protected Storage
• Upload files
• Update copy

NOTES:

This worm monitors the following instant messaging applications and views its threads:

• AIM Triton
MSN Messenger

In order to successfully connect to the IRC server, it uses the following credentials:

• Nick name: [USA|00|P|{number}]
• Password: shakawkaw