BKDR_NUPIC.RQ

 Analysis by: Pearl Charlaine Espejo

 ALIASES:

Backdoor:Win32/Nupic.A (Microsoft); Trojan.Win32.Pincav.adgo (Kaspersky); Trojan.Pincav (VBA32); Trojan.Win32.Pincav.caidl (NANO-Antivirus); W32/Pincav.ADGO!tr (Fortinet)

 PLATFORM:

Windows

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Downloaded from the Internet, Dropped by other malware


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

It runs certain commands that it receives remotely from a malicious user. Doing this puts the affected computer and information found on the computer at greater risk.

It retrieves specific information from the affected system.

It deletes the initially executed copy of itself.

  TECHNICAL DETAILS

File Size:

90,112 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

01 Oct 2015

Payload:

Compromises system security, Collects system information

Arrival Details

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

  • %Application Data%\checkdns.exe

(Note: %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 the following component file(s):

  • %WINDOWS%\msgpluse.dll - detected as BKDR_NUPIC.RQ

It adds the following processes:

  • iexplore.exe

It is injected into the following processes running in memory:

  • created iexplore.exe

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\{57098B79-D61B-4c35-98DE-5A042D455155}
StubPath = "%Application Data%\checkdns.exe"

Other System Modifications

This backdoor adds the following registry keys:

HKLM\SOFTWARE\Microsoft\
Active Setup\Installed Components\{57098B79-D61B-4c35-98DE-5A042D455155}

Backdoor Routine

This backdoor executes the following command(s) from a remote malicious user:

  • Enumerate files and folders
  • Enumerate fixed drives and retrieve free disk space
  • Delete files and folders
  • Download arbitrary files
  • Upload files
  • Execute cmd shell commands
  • Create a Process
  • Enumerate Processes and Modules
  • Terminate Process

It connects to the following URL(s) to send and receive commands from a remote malicious user:

  • http://mail.{BLOCKED}010.com:1863/net/{data}/{data}/searchnNewsNn2.php

As of this writing, the said sites are inaccessible.

Dropping Routine

This backdoor drops the following file(s), into which it saves gathered information:

  • %Windows%\mss{random characters}.tmp - where cmd shell commands output are piped into
  • %User Temp%\msextlog.dll - where cmd shell commands output are piped into
  • %User Temp%\msp{random characters}.tmp - where the enumerated processes and modules are saved
  • %User Temp%\mspli02.tmp - where the enumerated processes and modules are saved

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

Information Theft

This backdoor retrieves the following information from the affected system:

  • Host name
  • IP address
  • Proxy server

Other Details

This backdoor deletes the initially executed copy of itself

  SOLUTION

Minimum Scan Engine:

9.750

FIRST VSAPI PATTERN FILE:

11.952.02

FIRST VSAPI PATTERN DATE:

01 Oct 2015

VSAPI OPR PATTERN File:

11.953.00

VSAPI OPR PATTERN Date:

02 Oct 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 key

[ 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
    • {57098B79-D61B-4c35-98DE-5A042D455155}

Step 5

Search and delete these files

[ 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.
  • %Windows%\mss{random characters}.tmp
  • %User Temp%\msextlog.dll
  • %User Temp%\msp{random characters}.tmp
  • %User Temp%\mspli02.tmp

Step 6

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