RANSOM_ZLOCKER.THACAH

 Analysis by: Christian Noel Olalia

 ALIASES:

HEUR:Hoax.Win32.Generic (KASPERSKY); Trojan.Gen.2 (NORTON); Mal/ZLock-A (SOPHOS_LITE)

 PLATFORM:

Windows

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

  • Threat Type: Ransomware

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Dropped by other malware, Downloaded from the Internet

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 connects to certain websites to send and receive information.

It encrypts files found in specific folders. It drops files as ransom note.

  TECHNICAL DETAILS

File Size:

30,208 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

30 Jan 2018

Payload:

Connects to URLs/IPs, Displays message/message boxes, Encrypts files

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.

Other Details

This Ransomware connects to the following website to send and receive information:

  • https://api.{BLOCKED}am.org/bot379720942:AAEfoWyvUC0T2gY12T5PIsamNtZ1m2gmRTw/

Ransomware Routine

This Ransomware encrypts files found in the following folders:

  • C:\
  • D:\
  • E:\
  • F:\
  • G:\
  • {Malware Path}\
  • %Program Files%\
  • %Desktop%\
  • %Desktop%\Новая папка\
  • %Desktop%\Новая папка(2)\
  • %Desktop%\фото\
  • %Desktop%\1\
  • %Desktop%\учёба\
  • %Desktop%\документы\
  • %Desktop%\музыка\
  • C:\Users\Guchinov_2\Documents\Visual Studio 2013\Projects\Zlocker\Zlocker\bin\Debug\Получить\
  • My Pictures\
  • My Documents\
  • My Music\

(Note: %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.. %Desktop% is the desktop folder, where it usually is C:\Documents and Settings\{user name}\Desktop in Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\Desktop in 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 appends the following extension to the file name of the encrypted files:

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

  • {Encrypted File Path}\ВАШИ ФАЙЛЫ ЗАШИФРОВАНЫ.txt

  SOLUTION

Minimum Scan Engine:

9.850

FIRST VSAPI PATTERN FILE:

13.938.02

FIRST VSAPI PATTERN DATE:

31 Jan 2018

VSAPI OPR PATTERN File:

13.939.00

VSAPI OPR PATTERN Date:

01 Feb 2018

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

Identify and terminate files detected as RANSOM_ZLOCKER.THACAH

[ Learn More ]
  1. Windows Task Manager may not display all running processes. In this case, please use a third-party process viewer, preferably Process Explorer, to terminate the malware/grayware/spyware file. You may download the said tool here.
  2. If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
  3. If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.

Step 4

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.
  • {Encrypted file path}\ВАШИ ФАЙЛЫ ЗАШИФРОВАНЫ.txt

Step 5

Restore encrypted files from backup.


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