Ransom.Win32.CLOP.E

March 05, 2019
 Analysis by: Kiyoshi Obuchi
 Modified by: Arvin Roi Macaraeg
 ALIASES:

N/A

 PLATFORM:

Windows

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

  • Threat Type: Ransomware

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Downloaded from the Internet, Dropped by other malware

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

It drops files as ransom note.

  TECHNICAL DETAILS

File Size:

250,136 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

26 Feb 2019

Payload:

Terminates processes, Encrypts files, Displays message/message boxes

Arrival Details

This Ransomware 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 Ransomware drops the following files:

  • {Malware Path}\systempdisk_11_23_556_6.bat

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

  • HappyLife^_-

Autostart Technique

This Ransomware starts the following services:

  • Service Name: TaskNetProcess
    Service Type: 16

Process Termination

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

  • mysqld-opt.exe
  • xfssvccon.exe
  • thebat.exe
  • ocautoupds.exe
  • wordpad.exe
  • mysqld-nt.exe
  • thebat64.exe
  • excel.exe
  • thunderbird.exe
  • agntsvc.exeagntsvc.exe
  • zoolz.exe
  • msaccess.exe
  • sqlwriter.exe
  • WINWORD.EXE
  • THEBAT.EXE
  • VISIO.EXE
  • MSFTESQL.EXE
  • ORACLE.EXE
  • MYDESKTOPQOS.EXE

Other Details

This Ransomware does the following:

  • This Ransomware will delete itself:
    • If the keyboard layout is any of the following:
      • Georgian
      • Russian
      • Tajik
      • Belarusian
      • Armenian
      • Azeri
      • Kazak
      • Kyrgyz
    • If the default language ID is as follows:
      • Russian
  • It will drop and execute "{Malware Path}\systempdisk_11_23_556_6.bat" if the following processes are not found:
    • SBAMSvc.exe
    • VipreAAPSvc.exe
    • SBAMTray.exe
    • SBPIMSvc.exe
    • WRSA.exe
  • Executes the following commands to edit the boot configuration data file
    • bcdedit /set {default} recoveryenabled No
    • bcdedit /set {default} bootstatuspolicy ignoreallfailures
  • Executes the following commands to delete and resize the shadow copies:
    • vssadmin resize shadowstorage /for=h: /on=h: /maxsize=401MB
    • vssadmin resize shadowstorage /for=h: /on=h: /maxsize=unbounded
    • vssadmin Delete Shadows /all /quiet
  • It encrypts all files except the following:
    • .Clop
    • Clopreadme.txt
    • ntldr
    • NTLDR
    • boot.ini
    • BOOT.INI
    • ntuser.ini
    • NTUSER.INI
    • AUTOEXEC.BAT
    • autoexec.bat
    • NTDETECT.COM
    • ntdetect.com
    • .dll
    • .DLL
    • .exe
    • .EXE
    • .sys
    • .SYS
    • .OCX
    • .ocx
    • .LNK
    • .lnk
    • desktop.ini
    • autorun.inf
    • ntuser.dat
    • iconcache.db
    • bootsect.bak
    • ntuser.dat.log
    • thumbs.db
    • DESKTOP.INI
    • AUTORUN.INF
    • NTUSER.DAT
    • ICONCACHE.DB
    • bootsect.bak
    • NTUSER.DAT.LOG
    • THUMBS.DB
  • It encrypts files which can be found in the following locations:
    • Removable Drives
    • Fixed Drives
    • Shared Drives
  • the batch file "{Malware Path}\systempdisk_11_23_556_6.bat" contains the following strings:
    • @echo off
      vssadmin Delete Shadows /all /quiet
      vssadmin resize shadowstorage /for=c: /on=c: /maxsize=401MB
      vssadmin resize shadowstorage /for=c: /on=c: /maxsize=unbounded
      vssadmin resize shadowstorage /for=d: /on=d: /maxsize=401MB
      vssadmin resize shadowstorage /for=d: /on=d: /maxsize=unbounded
      vssadmin resize shadowstorage /for=e: /on=e: /maxsize=401MB
      vssadmin resize shadowstorage /for=e: /on=e: /maxsize=unbounded
      vssadmin resize shadowstorage /for=f: /on=f: /maxsize=401MB
      vssadmin resize shadowstorage /for=f: /on=f: /maxsize=unbounded
      vssadmin resize shadowstorage /for=g: /on=g: /maxsize=401MB
      vssadmin resize shadowstorage /for=g: /on=g: /maxsize=unbounded
      vssadmin resize shadowstorage /for=h: /on=h: /maxsize=401MB
      vssadmin resize shadowstorage /for=h: /on=h: /maxsize=unbounded
      vssadmin Delete Shadows /all /quiet
      bcdedit /set {default} recoveryenabled No
      bcdedit /set {default} bootstatuspolicy ignoreallfailures

Ransomware Routine

This Ransomware appends the following extension to the file name of the encrypted files:

  • {file name}.{file extension}.Clop

It drops the following file(s) as ransom note:

  SOLUTION

Minimum Scan Engine:

9.850

FIRST VSAPI PATTERN FILE:

14.838.02

FIRST VSAPI PATTERN DATE:

26 Feb 2019

VSAPI OPR PATTERN File:

14.839.00

VSAPI OPR PATTERN Date:

27 Feb 2019

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

Disable this malware service

[ Learn More ]
    • Service Name: TaskNetProcess

Step 5

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.
  • {Malware Path}\systempdisk_11_23_556_6.bat

Step 6

Restart in normal mode and scan your computer with your Trend Micro product for files detected as Ransom.Win32.CLOP.E. 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 7

Restore encrypted files from backup.


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