Analysis by: Jeanne Jocson

 PLATFORM:

Windows

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel: Downloaded from the Internet

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

However, as of this writing, the said sites are inaccessible.

  TECHNICAL DETAILS

File Size: 1,324,544 bytes
File Type: EXE
Memory Resident: Yes
Payload: Connects to URLs/IPs

Arrival Details

This Trojan 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 Trojan drops the following copies of itself into the affected system and executes them:

  • %System%\{file name}.exe <- modified copy
    where {file name} can be any of the following:
    • wmiapsrvce
    • wmipsrvce
    • wmiapsrvcep
    • wmiapsvrce
    • wmipsvrce
    • wmiapsvrcep
    • wmiapsvre
    • wmipsvre
    • wmiapsvrep
    • wmiapvsre
    • wmipvsre
    • wmiapvsrep
    • wmiaprvse
    • wmiprvse
    • wmiaprvsep
    Executes using the following shell code:
    • cmd.exe /c start /b "" %System%{file name}.exe dwPlatform=1 fPlatform=0

(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

It drops and executes the following files:

  • %System%\{DLL Name}.dll-detected by Trend Micro as TROJ_KWAMPIRS.SMA
    where {DLL name} can be any of the following:
    • wmiamgmt
    • wmiassn
    • wmipadp
    • wmiadrv
    • wmipdpa
    Executes using the following shell code:
    • rundll32.exe "%System%\{DLL name}.dll" ControlTrace -Embedding -k DcomLaunch

(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

Autostart Technique

This Trojan adds and runs the following services:

  • Service Name: WmiApSrvEx
    Display Name: WMI Performance Adapter Extension
    Start Type: SERVICE_AUTO_START
    Binary Pathname: %System%\{malware name}.exe

(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

Other System Modifications

This Trojan deletes the following files:

  • Previous copies of Itself
  • Previous dropped DLL components

Process Termination

This Trojan terminates the following processes if found running in the affected system's memory:

  • Running Processes of Itself
  • Its own DLL modules running under rundll32.exe

Dropping Routine

This Trojan drops the following files:

  • %User Temp%\{random}.tmp <- temporary file for creating its drop files, deleted after
  • %Windows%\inf\mtmndkb32.PNF
  • %Windows%\inf\ie11.PNF
  • %Windows%\inf\mkdiawb3.PNF
  • %Windows%\inf\digirps.PNF

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp 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.. %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.)

Other Details

This Trojan does the following:

  • Reads data/code on its created pipe if available. The received data/code is expected to be executed in the memory of the malware process. However, as of this writing, there were no data received.
  • Checks if running in 32bit environment to disable 64bit redirection of the system folder
  • Changes the file time of dropped copy and dll component
  • Requests data from the following URLs via HTTP GET:
    • http://{BLOCKED}.{BLOCKED}.41.39/groupusers/index.asp?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.100.90/usersgroup/home.asp?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.80.23/newusers/homemain/home.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.139.145/users/default/main.aspx?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.119.64/defaultdefaultlogin.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.134.10/groupusers/default.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.88.108/login.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.122.119/users/users/homeindex/login.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.113.103/usersgroup/home/login/login.asp?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.111.123/new/main.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.7.75/main.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.58.70/group/default.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.49.129/group/new/login.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.13.91/group/default/defaultlogin.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.115.97/default.asp?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.47.135/group/homeindex.asp?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.28.10/new/main.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.120.32/new/login.asp?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.111.25/new/main/defaultlogin.asp?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.28.56/usersusers/home.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.36.113/new/users/mainindex.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.98.115/group/indexhomeindex.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.83.94/homeindexindex.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.18.57/main.aspx?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.34.33/default.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.35.77/newusers/loginindex.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.33.82/usersnew/login/loginindex.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.49.78/users/new/main/login.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.29.20/new/login/login.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.54.140/new/maindefault/default.aspx?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.92.107/group/defaultdefaultdefault.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.74.28/usersgroup/main.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.140.76/homemainmain.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.28.42/group/default/main/default.asp?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.92.7/default/login.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.10.68/new/login.aspx?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.110.69/default.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.39.144/usersusers/home.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.19.59/index/index/main.aspx?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.9.114/groupusers/main.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.137.20/group/homedefault.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.100.90/usersgroup/home.asp?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.80.23/newusers/homemain/home.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.139.145/users/default/main.aspx?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.119.64/defaultdefaultlogin.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.134.10/groupusers/default.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.88.108/login.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.122.119/users/users/homeindex/login.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.113.103/usersgroup/home/login/login.asp?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.111.123/new/main.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.7.75/main.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.58.70/group/default.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.49.129/group/new/login.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.13.91/group/default/defaultlogin.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.115.97/default.asp?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.47.135/group/homeindex.asp?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.54.90/default.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.137.35/main/default.asp?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.79.40/users/main.asp?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.89.112/new/homemain/main.aspx?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.149.207/index.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.30.28/new/main.php?q={encrypted data}
    • http://{BLOCKED}.{BLOCKED}.107.52/groupgroup/default.aspx?q={encrypted data}

However, as of this writing, the said sites are inaccessible.

  SOLUTION

Minimum Scan Engine: 9.800
FIRST VSAPI PATTERN FILE: 12.692.06
FIRST VSAPI PATTERN DATE: 03 Aug 2016

Step 1

Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.

Step 2

Remove malware/grayware files dropped/downloaded by TROJ_KWAMPIRS.SMB. (Note: Please skip this step if the threats listed below have already been removed.)

Step 3

Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.

Step 4

Restart in Safe Mode

[ Learn More ]

Step 5

Disable this malware service

[ Learn More ]
  •  WmiApSrvEx

Step 6

Search and delete this file

[ Learn More ]
There may be some 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%\{file name}.exe
  • %User Temp%\{random}.tmp
  • %Windows%\inf\mtmndkb32.PNF
  • %Windows%\inf\digirps.PNF
  • %Windows%\inf\ie11.PNF
  • %Windows%\inf\mkdiawb3.PNF

Step 7

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