WORM64_FOLDLER.A

This worm arrives via removable drives. 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 uses the default Windows folder icon to trick users into opening the file. Double-clicking the file executes this malware.

It drops copies of itself into network drives.

Arrival Details

This worm arrives via removable drives.

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 uses the default Windows folder icon to trick users into opening the file. Double-clicking the file executes this malware.

Other System Modifications

This worm modifies the following registry entries:

HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows\CurrentVersion\Policies\
System
ConsentPromptBehaviorAdmin = "0"

(Note: The default value data of the said registry entry is "5".)

Propagation

This worm drops the following copies of itself in all physical and removable drives:

• {drive letter}:\{original folder name}.exe

It drops copies of itself into network drives.

Download Routine

This worm connects to the following website(s) to download and execute a malicious file:

• {BLOCKED}videos.xyz/ext/go.exe (detected as TROJ64_EXTENBRO.AJ)

It saves the files it downloads using the following names:

• %Application Data%\svchosts.exe ( detected as TROJ64_EXTENBRO.AJ )

(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

NOTES:

It tries to copy itself to mounted CD drives.

It hides the folders on the drives that it infects and disguises its copies as the original folder.

It connects to the following URLs to download non-malicious files

• http://whos.{BLOCKED}ng.us/small/00/{random digits}.png