ALIASES:

Trojan.Gen.2 (Symantec); HEUR:Trojan.Win32.Generic (Kaspersky); Troj/MSIL-JHH (Sophos); Trojan.Win32.Generic!BT (Sunbelt)

 PLATFORM:

Windows

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

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.

  TECHNICAL DETAILS

File Size: 975,968 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 30 Jun 2017

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:

  • %User Temp%\FolderN\name.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.)

It creates the following folders:

  • %User Profile%\AppData
  • %User Profile%\AppData\Local
  • %User Profile%\Local\Temp
  • %User Profile%\Temp\FolderN
  • %User Profile%\Application Data\Monitor
  • %Program Files%\Client
  • %User Profile%\Monitor\Logs
  • %User Profile%\Monitor\Files
  • %User Profile%\Monitor\Guard
  • %User Profile%\Monitor\Screenshots
  • %User Profile%\Screenshots\06-14-2017

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.. %Program Files% is the Program Files folder, where it usually is C:\Program Files on all Windows operating system versions; C:\Program Files (x86) for 32-bit applications running on Windows 64-bit operating systems.)

Autostart Technique

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\RunOnce
Client Monitor = "cmd /c start Client Monitor %Program Files%\Client\client.exe "

Other System Modifications

This Backdoor deletes the following files:

  • %User Profile%\Temp\ svhost.exe
  • %User Profile%\FolderN\name.exe:Zone.Identifier
  • %User Startup%\name.exe:Zone.Identifier
  • %Program Files%\Client\client.exe:Zone.Identifier

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.. %User Startup% is the current user's Startup folder, which is usually C:\Documents and Settings\{user}\Start Menu\Programs\Startup on Windows 2000 and XP, and C:\Documents and Settings\{User name}\Start Menu\Programs\Startup on Windows Vista, 7, and 8.. %Program Files% is the Program Files folder, where it usually is C:\Program Files on all Windows operating system versions; C:\Program Files (x86) for 32-bit applications running on Windows 64-bit operating systems.)

It adds the following registry keys:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Control\MediaResources\msvideo

It adds the following registry entries:

HKEY_CURRENT_USER\Software
MgQnCESSb6/1FP70cjugiA== = "JFMZD5WpiAesGVjXEzr+dm4DNZKVc0VdXkWq25UT/5Q="

HKEY_CURRENT_USER\Software
yZUhOPHDu1qzofSDMW3sFA== = "N7O9fqOsQQZGC9U87sYElQ=="

HKEY_CURRENT_USER\Software
RQucpmMjE2cx7v/Gkzfssw== = "mYYAjVehOJOazGv3o9JXXw=="

HKEY_CURRENT_USER\Software\Microsoft\
Windows NT\CurrentVersion\Winlogon
shell = "explorer.exe,%System%\clientmonitor.exe "

HKEY_CURRENT_USER\Software
FfKUVWqpoMx2wWYc48MJpw== = "CmQyDdvLYaK2Hq643MdXyfjxOw41sCBv0K9AJdU64yM="

HKEY_CURRENT_USER\Software
RQucpmMjE2cx7v/Gkzfssw== = "18cwh5lLrzAfkU6ETpLXBw=="

HKEY_CURRENT_USER\Software
bapyVDyJZouQL34mUQ8AzA== = "7NieXrjzYbfVYel8KuKNLQ=="

HKEY_CURRENT_USER\Software
du5bidbSILHeiqunIBMZ6GWNSRmZsNyePupaqRG61A4= = "LAvD8vgYe48NSxutSvNCrQ=="

HKEY_CURRENT_USER\Software
pDzxE1IOcuBgBLGMlPOL5ywLw/L4GHuPDUsbrUrzQq0= = "LAvD8vgYe48NSxutSvNCrQ=="

HKEY_CURRENT_USER\Software
qpzfrdfgD4IMVWYXHu089g== = "{random characters}"

It modifies the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows NT\CurrentVersion\Windows
Load = "%User Temp%\FolderN\name.exe.lnk "

Dropping Routine

This Backdoor drops the following files:

  • %User Profile%\FolderN\name.exe.lnk
  • %User Profile%\Guard\1
  • %User Profile%\06-14-2017\2.27 AM
  • %User Temp%\6124
  • %User Profile%\Temp\svhost.exe
  • %Program Files%\Client\client.exe
  • %System%\clientmonitor.exe

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.. %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.. %Program Files% is the Program Files folder, where it usually is C:\Program Files on all Windows operating system versions; C:\Program Files (x86) for 32-bit applications running on Windows 64-bit operating systems.. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

Other Details

This Backdoor connects to the following possibly malicious URL:

  • {BLOCKED}7.99.182

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine: 9.8

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

Restart in Safe Mode

[ Learn More ]

Step 3

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\SYSTEM\CurrentControlSet\Control\MediaResources
    • msvideo

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.

  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\RunOnce
    • Client Monitor = "cmd /c start Client Monitor %Program Files%\Client\client.exe "
  • In HKEY_CURRENT_USER\Software
    • MgQnCESSb6/1FP70cjugiA== = "JFMZD5WpiAesGVjXEzr+dm4DNZKVc0VdXkWq25UT/5Q="
  • In HKEY_CURRENT_USER\Software
    • yZUhOPHDu1qzofSDMW3sFA== = "N7O9fqOsQQZGC9U87sYElQ=="
  • In HKEY_CURRENT_USER\Software
    • RQucpmMjE2cx7v/Gkzfssw== = "mYYAjVehOJOazGv3o9JXXw=="
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Winlogon
    • shell = "explorer.exe,%System%\clientmonitor.exe "
  • In HKEY_CURRENT_USER\Software
    • FfKUVWqpoMx2wWYc48MJpw== = "CmQyDdvLYaK2Hq643MdXyfjxOw41sCBv0K9AJdU64yM="
  • In HKEY_CURRENT_USER\Software
    • RQucpmMjE2cx7v/Gkzfssw== = "18cwh5lLrzAfkU6ETpLXBw=="
  • In HKEY_CURRENT_USER\Software
    • bapyVDyJZouQL34mUQ8AzA== = "7NieXrjzYbfVYel8KuKNLQ=="
  • In HKEY_CURRENT_USER\Software
    • du5bidbSILHeiqunIBMZ6GWNSRmZsNyePupaqRG61A4= = "LAvD8vgYe48NSxutSvNCrQ=="
  • In HKEY_CURRENT_USER\Software
    • pDzxE1IOcuBgBLGMlPOL5ywLw/L4GHuPDUsbrUrzQq0= = "LAvD8vgYe48NSxutSvNCrQ=="
  • In HKEY_CURRENT_USER\Software
    • qpzfrdfgD4IMVWYXHu089g== = "{random characters}"

Step 5

Restore these modified registry values

[ Learn More ]

Important:Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this only if you know how to or you can seek your system administrator's help. You may also check out this Microsoft article first before modifying your computer's registry.

  • In HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Windows
    • Load = "%User Temp%\FolderN\name.exe.lnk "

Step 6

Search and delete these components

[ Learn More ]
There may be some components 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.
  • %User Profile%\FolderN\name.exe.lnk
  • %User Profile%\Guard\1
  • %User Profile%\06-14-2017\2.27 AM
  • %User Temp%\6124
  • %User Profile%\Temp\svhost.exe
  • %Program Files%\Client\client.exe
  • %System%\clientmonitor.exe

Step 7

Search and delete these folders

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
  • %User Profile%\AppData
  • %User Profile%\AppData\Local
  • %User Profile%\Local\Temp
  • %User Profile%\Temp\FolderN
  • %User Profile%\Application Data\Monitor
  • %Program Files%\Client
  • %User Profile%\Monitor\Logs
  • %User Profile%\Monitor\Files
  • %User Profile%\Monitor\Guard
  • %User Profile%\Monitor\Screenshots
  • %User Profile%\Screenshots\06-14-2017

Step 8

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

Step 9

Restore this file from backup only Microsoft-related files will be restored. If this malware/grayware also deleted files related to programs that are not from Microsoft, please reinstall those programs on you computer again.

  • %User Profile%\Temp\ svhost.exe
  • %User Profile%\FolderN\name.exe:Zone.Identifier
  • %User Startup%\name.exe:Zone.Identifier
  • %Program Files%\Client\client.exe:Zone.Identifier


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