PE_LICAT.A-O

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

It inserts its codes into unused space in files.

It opens a random port to allow a remote user to connect to the affected system. Once a successful connection is established, the remote user executes commands on the affected system.

It attempts to steal sensitive online banking information, such as user names and passwords. This routine risks the exposure of the user's account information, which may then lead to the unauthorized use of the stolen data.

Arrival Details

This file infector 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 file infector drops the following copies of itself into the affected system:

• %Application Data%\{random1}\{random}.exe

(Note: %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 component file(s):

• %Application Data%\{random2}\{random}.{3 random alpha character extension name}

(Note: %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 injects itself into the following processes running in the affected system's memory:

• explorer.exe

It creates the following folders:

• %Application Data%\{random1}
• %Application Data%\{random2}

(Note: %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.)

Autostart Technique

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{GUID} = "%Application Data%\{random1}\{random}.exe"

Other System Modifications

This file infector adds the following registry keys as part of its installation routine:

HKEY_CURRENT_USER\Software\Microsoft\
{random}

File Infection

This file infector infects the following file types:

• .EXE

It inserts its codes into unused space in files.

It avoids infecting folders containing the following strings:

• %Program Files%
• %System%
• %User Application Data%
• %Windows%

(Note: %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000, Server 2003, and XP (32-bit), Vista (32-bit), and 7 (32-bit), or C:\Program Files (x86) in Windows XP (64-bit), Vista (64-bit), and 7 (64-bit).. %System% is the Windows system folder, which is usually C:\Windows\System32.. %Windows% is the Windows folder, which is usually C:\Windows.)

Backdoor Routine

This file infector opens a random port to allow a remote user to connect to the affected system. Once a successful connection is established, the remote user executes commands on the affected system.

Information Theft

This file infector attempts to steal sensitive online banking information, such as user names and passwords. This routine risks the exposure of the user's account information, which may then lead to the unauthorized use of the stolen data.

NOTES:

This worm generates pseudorandom alpha characters using a randomizing function, which is computed from the current UTC system date and time. It then creates 800 domain names at every execution based from the generated characters and appends any of the following to complete a URL:

• .biz/forum
• .org/forum
• .info/forum
• .net/forum
• .com/forum

It then connects to its generated URLs to donwload file(s). However, as of this writing, the said sites are inaccessible.

Infected files are detected as PE_LICAT.A.