Analysis by: Rika Joi Gregorio
 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

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

It modifies registry entries to hide files with System and Read-only attributes.

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

  TECHNICAL DETAILS

File Size: 176,128 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 23 Nov 2012

Arrival Details

This worm 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:

  • %UserProfile%\{random}.exe
  • %UserProfile%\Passwords.exe
  • %UserProfile%\Porn.exe
  • %UserProfile%\Secret.exe
  • %UserProfile%\Sexy.exe

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
{random} = "%User Profile%\{random}.exe /r"

Other System Modifications

This worm adds the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Policies\
Microsoft\Windows\WindowsUpdate\
AU

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Policies\
Microsoft\Windows\WindowsUpdate\
AU
NoAutoUpdate = "00000001"

It modifies the following registry entries to hide files with System and Read-only attributes:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
ShowSupperHidden = "00000001"

(Note: The default value data of the said registry entry is 00000000.)

Propagation

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

  • {Drive Letter}\Porn.exe
  • {Drive Letter}\Secret.exe
  • {Drive Letter}\Sexy.exe
  • {Drive Letter}\{random}.exe
  • {Drive Letter}\Passwords.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:

[autorun]
open={RANDOM}.eXE
AcTiOn=23199
usEAutopLAy=1

Other Details

This worm connects to the following possibly malicious URL:

  • {BLOCKED}.{BLOCKED}dater.net