BKDR_POISONDLD.A

 Analysis by: Erika Bianca Mendoza

 ALIASES:

Trojan.Generic.7044544 (F-Secure); Trojan.Win32.Jorik.PoisonIvy.rr (Kaspersky); Generic.bfr!dl (McAfee); TrojanDownloader:Win32/Poison.A (Microsoft); Trojan.Gen (Symantec); Win-Trojan/Jorik.20480.K (AhnLab-V3); Win32:VB-AAGN [Trj] (Avast); Downloader.VB.RYP (AVG); Trojan.Generic.7044544 (BitDefender); Trojan.Poison-1503 (ClamAV); W32/DwnLdr.JNS!tr (Fortinet); Trojan.Generic.7044544 (GData); Trojan.Win32.Jorik (Ikarus); Trojan/Jorik.ache (Jiangmin); W32/Suspicious_Gen2.UAJPE (Norman); Trojan.Win32.Generic!BT (VIPRE); Trojan.Agent!HaisdJ8N1Uw (VirusBuster)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

This backdoor may be unknowingly downloaded by a user while visiting malicious websites.

It opens a hidden Internet Explorer window.

  TECHNICAL DETAILS

File Size:

20,480 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

01 Feb 2012

Payload:

Downloads files

Arrival Details

This backdoor may be unknowingly downloaded by a user while visiting malicious websites.

Installation

This backdoor drops the following files:

  • %System%\misys

(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)

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

  • %System%\misys.exe

(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)

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

  • !VaqA.I4

It is injected into the following processes running in memory:

  • explorer.exe
  • msnmsgr.exe
  • default browser

Autostart Technique

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Active Setup\Installed Components\{55AB1BE6-FDF1-703C-25BA-48DD3A2DD6E7}
StubPath = "%System%\misys.exe"

Other Details

This backdoor opens a hidden Internet Explorer window.

NOTES:

Upon execution, this backdoor downloads and executes a shellcode from the following URL and executes it:

  • http://{BLOCKED}ftibet.net/1207.html

As of this writing, the downloaded code is a variant of BKDR_POISON malware family. As a result, the routines of the said malware are also exhibited in the system.

The downloaded backdoor queries the value in the registry below to obtain the system's default browser:

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\http\shell\open\command

It then creates a hidden instance of the default browser and injects backdoor code into it.

It also connects to the C&C server dd.ip{BLOCKED}hq.com and uses the password admin.

Once connected, it is capable of doing the following routines:

  • Capture screenshots, audio, video
  • Delete, search and upload files
  • Download and inject codes into legitimate processes
  • Manage processes and services
  • Modify and search registry entries
  • Perform shell command
  • Send system information (IP address, computer name, user name, operating system)

It also has a feature to log keystrokes and mouse events using the SetWindowsEx API. The logs are saved in the file %System%\misys.

  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_LOCAL_MACHINE\SOFTWARE\Microsoft\Active Setup\Installed Components\{55AB1BE6-FDF1-703C-25BA-48DD3A2DD6E7}
    • StubPath = "%System%\misys.exe"

Step 4

Search and delete this file

[ Learn More ]
There may be some component files that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden files and folders in the search result.
  • %System%\misys

Step 5

Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_POISONDLD.A. 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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