Analysis by: Cris Nowell Pantanilla

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

Infection Channel: Spammed via email

This backdoor arrives as an attachment to email messages spammed by other malware/grayware or malicious users.

It connects to a website to send and receive information.

  TECHNICAL DETAILS

File Size: 58,880 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 26 Mar 2012
Payload: Compromises system security, Connects to URLs/IPs, Steals information, Drops files

Arrival Details

This backdoor arrives as an attachment to email messages spammed by other malware/grayware or malicious users.

Installation

This backdoor drops the following files:

  • %User Temp%\{random}.tmp - also detected as BKDR_INJECT.HBAH

(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 drops the following copies of itself into the affected system:

  • %User Profile%\Application Data\skyphone.exe

(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.)

It injects codes into the following process(es):

  • IEXPLORE.EXE

Autostart Technique

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
SKYLINE = "%User Profile\Application Data\skyphone.exe"

Backdoor Routine

This backdoor connects to the following websites to send and receive information:

  • {BLOCKED}nline.redirectme.net:443
  • {BLOCKED}gh.ddns.info:1863

NOTES:
It queries the default web browser by accessing the following registry entry:

HKEY_CLASSES_ROOT\http\shell\open\command

It then launches a hidden Web browser process (e.g. iexplore.exe) where this malware injects its code for its backdoor routines. It is capable of the following commands:

  • Create,Search, and Delete Files
  • Download and inject remote codes to legitimate processes
  • Download and Upload Files
  • Log keystrokes and active window
  • Manage processes and services
  • Modify and search the registry entries
  • Perform a shell command
  • Send system information (IP address, computer name, user name, operating system)
  • Update/Uninstall the malware
  • View and terminate active windows and ports

  SOLUTION

Minimum Scan Engine: 9.200

Step 1

For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.

Step 2

Restart in Safe Mode

[ Learn More ]

Step 3

Delete this registry value

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

 
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • SKYLINE = "%User Profile\Application Data\skyphone.exe"

Step 4

Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_INJECT.HBAH. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.


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