Modified by: Jimelle Monteser
ALIASES:

Backdoor.Win32.Morix (Ikarus), Backdoor:Win32/Morix.B (Microsoft)

 PLATFORM:

Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel: Dropped by other malware, Downloaded from the Internet

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 uses Windows Task Scheduler to create a scheduled task that executes the dropped copy.

It executes commands from a remote malicious user, effectively compromising the affected system. It connects to a website to send and receive information.

  TECHNICAL DETAILS

File Size: 87,040 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 27 Mar 2014
Payload: Drops files, Terminates processes, Compromises system security

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:

  • %Windows%\92E2EA8E\svchsot.exe

(Note: %Windows% is the Windows folder, which is usually C:\Windows.)

It uses Windows Task Scheduler to create a scheduled task that executes the dropped copy.

It creates the following folders:

  • %Windows%\92E2EA8E

(Note: %Windows% is the Windows folder, which is usually C:\Windows.)

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\Run
92E2EA8E = "%Windows%\92E2EA8E\svchsot.exe"

The scheduled task executes the malware every:

  • 1 hour (everyday)

Other System Modifications

This backdoor adds the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\Schedule
AtTaskMaxHours = "48"

It modifies the following registry key(s)/entry(ies) as part of its installation routine:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\Schedule
NextAtJobId = "19"

(Note: The default value data of the said registry entry is "1".)

Backdoor Routine

This backdoor executes the following commands from a remote malicious user:

  • Download files
  • Perform remote shell command
  • Manage services
  • Manage processes
  • Manage windows
  • Capture screenshots

It connects to the following websites to send and receive information:

  • {BLOCKED}d.{BLOCKED}nn.com:1111

Process Termination

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

  • avp.exe
  • Rstray.exe
  • KSafeTray.exe
  • 360tray.exe
  • KvMonXP.exe
  • egui.exe
  • kxetray.exe

Dropping Routine

This backdoor drops the following files:

  • %Windows%\Task\At1.job
  • %Windows%\Task\At2.job
  • %Windows%\Task\At3.job
  • %Windows%\Task\At4.job
  • %Windows%\Task\At5.job
  • %Windows%\Task\At6.job
  • %Windows%\Task\At7.job
  • %Windows%\Task\At8.job
  • %Windows%\Task\At9.job
  • %Windows%\Task\At10.job
  • %Windows%\Task\At11.job
  • %Windows%\Task\At12.job
  • %Windows%\Task\At13.job
  • %Windows%\Task\At14.job
  • %Windows%\Task\At15.job
  • %Windows%\Task\At16.job
  • %Windows%\Task\At17.job
  • %Windows%\Task\At18.job
  • %Windows%\Task\At19.job
  • %Windows%\Task\At20.job
  • %Windows%\Task\At21.job
  • %Windows%\Task\At22.job
  • %Windows%\Task\At23.job
  • %Windows%\Task\At24.job

(Note: %Windows% is the Windows folder, which is usually C:\Windows.)

Information Theft

This backdoor gathers the following data:

  • Processor Speed
  • ComputerName
  • OS Version
  • Drive Information

  SOLUTION

Minimum Scan Engine: 9.700
FIRST VSAPI PATTERN FILE: 10.690.03
FIRST VSAPI PATTERN DATE: 27 Mar 2014
VSAPI OPR PATTERN File: 10.691.00
VSAPI OPR PATTERN Date: 28 Mar 2014

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 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\Run
    • 92E2EA8E = "%Windows%\92E2EA8E\svchsot.exe"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Schedule
    • AtTaskMaxHours = "48"

Step 4

Restore this modified registry value

[ 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_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Schedule
    • From: NextAtJobId = "19"
      To: NextAtJobId = "1"

Step 5

Search and delete this folder

[ 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.
  • %Windows%\92E2EA8E

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.
  • %Windows%\Task\At1.job
  • %Windows%\Task\At2.job
  • %Windows%\Task\At3.job
  • %Windows%\Task\At4.job
  • %Windows%\Task\At5.job
  • %Windows%\Task\At6.job
  • %Windows%\Task\At7.job
  • %Windows%\Task\At8.job
  • %Windows%\Task\At9.job
  • %Windows%\Task\At10.job
  • %Windows%\Task\At11.job
  • %Windows%\Task\At12.job
  • %Windows%\Task\At13.job
  • %Windows%\Task\At14.job
  • %Windows%\Task\At15.job
  • %Windows%\Task\At16.job
  • %Windows%\Task\At17.job
  • %Windows%\Task\At18.job
  • %Windows%\Task\At19.job
  • %Windows%\Task\At20.job
  • %Windows%\Task\At21.job
  • %Windows%\Task\At22.job
  • %Windows%\Task\At23.job
  • %Windows%\Task\At24.job

Step 7

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