Analysis by: Sammy Chua
 Modified by: Homer Pacag

ALIASES:

Trojan.Mentono (Symantec)

 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

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.

  TECHNICAL DETAILS

File Size: 1,756,114 bytes
File Type: EXE
Memory Resident: Yes

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 files:

  • %User Temp%folder\ortmp\freebl3.dll - deleted afterwards
  • %User Temp%folder\ortmp\libnspr4.dll - deleted afterwards
  • %User Temp%folder\ortmp\libplc4.dll - deleted afterwards
  • %User Temp%folder\ortmp\libplds4.dll - deleted afterwards
  • %User Temp%folder\ortmp\nss3.dll - deleted afterwards
  • %User Temp%folder\ortmp\nssckbi.dll - deleted afterwards
  • %User Temp%folder\ortmp\nssdbm3.dll - deleted afterwards
  • %User Temp%folder\ortmp\nssutil3.dll - deleted afterwards
  • %User Temp%folder\ortmp\smime3.dll - deleted afterwards
  • %User Temp%folder\ortmp\softokn3.dll - deleted afterwards
  • %User Temp%folder\ortmp\sqlite3.dll - deleted afterwards
  • %User Temp%folder\ortmp\ssl3.dll - deleted afterwards
  • %System%\lub\gatc\ujed.dat - contains site redirections
  • %Application Data%\ortmp\uninstaller.exe

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

It drops and executes the following files:

  • %User Temp%folder\ortmp\orion.exe - detected as TROJ_NOPLE.A

(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.)

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

  • Global\Matil da

Autostart Technique

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\RunOnce
cmdrun = cmd.exe /C ipconfig /flushdns

Other System Modifications

This Trojan adds the following registry entries as part of its installation routine:

HKEY_LOCAL_MACHINE\SOFTWARE\daugava
version = 2.0.0.702

HKEY_LOCAL_MACHINE\SOFTWARE\daugava
product_version = 2.0.0.702

NOTES:

This malware modifies %System%\dnsapi.dll, detected as PTCH_NOPLE.SM, to access the dropped file %System%\lub\gatc\ujed.dat.

This malware also checks if the following anti-virtual machine programs are running and terminates if found:

  • VBOX
  • VMWARE
  • Sandboxie

  SOLUTION

Minimum Scan Engine: 9.800
FIRST VSAPI PATTERN FILE: 11.924.06
FIRST VSAPI PATTERN DATE: 17 Sep 2015
VSAPI OPR PATTERN File: 11.925.00
VSAPI OPR PATTERN Date: 18 Sep 2015

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

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 3

Restart in Safe Mode

[ Learn More ]

Step 4

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.

  • HKEY_LOCAL_MACHINE\SOFTWARE\daugava

Step 5

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\Windows\CurrentVersion\RunOnce
    • cmdrun = cmd.exe /C ipconfig /flushdns

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%\lub\gatc\ujed.dat
  • %Application Data%\ortmp\uninstaller.exe
  • %User Temp%folder\ortmp\orion.exe

Step 7

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