Analysis by: Joshua Paul Ignacio
ALIASES:

Ransom:Win32/Ragnar!MSR (MICROSOFT); Trojan-Ransom.Ragnarlocker (IKARUS)

 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 drops files as ransom note. It avoids encrypting files with the following file extensions.

  TECHNICAL DETAILS

File Size: 50,176 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 22 May 2020
Payload: Terminates processes, 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.

Installation

This Ransomware adds the following processes:

  • wmic.exe shadowcopy delete → deletes shadow copies
  • vssadmin delete shadows /all /quiet → deletes shadow copies

Process Termination

This Ransomware terminates processes or services that contain any of the following strings if found running in the affected system's memory:

  • backup
  • connectwise
  • Dfs
  • logme
  • logmein
  • memtas
  • mepocs
  • mysql
  • pulseway
  • sophos
  • splashtop
  • sql
  • veeam
  • vmcompute
  • vmms
  • vss
  • agntsvc
  • benetns
  • bengine
  • beremote
  • beserver
  • dbeng50
  • dbsnmp
  • dfsrs.exe
  • dfssvc.exe
  • EduLink2SIMS
  • encsvc
  • excel
  • fdhost
  • firefox
  • infopath
  • isqlplussvc
  • msaccess
  • mspub
  • mydesktopqos
  • mydesktopservice
  • ocautoupds
  • ocomm
  • ocssd
  • onenote
  • oracle
  • outlook
  • OWSTIMER
  • postgres
  • powerpnt
  • pvlsvr
  • SAVAdminService
  • SavService.exe
  • sqbcoreservice
  • steam
  • swc_service.exe
  • synctime
  • tbirdconfig
  • thebat
  • thunderbird
  • visio
  • VxLockdownServer
  • winword
  • wordpad
  • WSSADMIN
  • wsstracing
  • xfssvccon

Other Details

This Ransomware does the following:

  • It checks for the computer's language and terminates itself if any the following language is detected:
    • Armenian
    • Azerbaijani
    • Belorussian
    • Georgian
    • Kazakh
    • Kyrgyz
    • Moldavian
    • Russian
    • Tajik
    • Turkmen
    • Ukrainian
    • Uzbek

It accepts the following parameters:

  • -backup
    • deletes shadow copies only
  • -list {Text File}
    • deletes shadow copies and encrypts only the directories indicated on the text file
  • -force {Path}
    • deletes shadow copies and encrypts only the path provided
  • -vm
    • deletes shadow copies and encrypts the whole machine avoiding files,folders and file extensions stated below.

Ransomware Routine

This Ransomware avoids encrypting files with the following strings in their file name:

  • RGNR_{8 Characters based on Computer Name}.txt
  • autorun.inf
  • boot.ini
  • bootfont.bin
  • bootsect.bak
  • bootmgr
  • bootmgr.efi
  • bootmgfw.efi
  • desktop.ini
  • iconcache.db
  • ntldr
  • ntuser.dat
  • ntuser.dat.log
  • ntuser.ini
  • thumbs.db

It avoids encrypting files found in the following folders:

  • Windows
  • Windows.old
  • Tor browser
  • Internet Explorer
  • Google
  • Opera
  • Opera Software
  • Mozilla
  • Mozilla Firefox
  • $Recycle.Bin
  • ProgramData
  • All Users

It renames encrypted files using the following names:

  • {Original Filename}.{Original File Extension}.ragnar_{8 Characters based on Computer Name}

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

  • %Public%\Documents\RGNR_{8 Characters based on Computer Name}.txt
  • {Encrypted Directory}\RGNR_{8 Characters based on Computer Name}.txt

(Note: %Public% is the folder that serves as a repository of files or folders common to all users, which is usually C:\Users\Public in Windows Vista, 7, and 8.)

It leaves text files that serve as ransom notes containing the following text:

It avoids encrypting files with the following file extensions:

  • .db
  • .sys
  • .dll
  • .lnk
  • .msi
  • .drv
  • .exe

  SOLUTION

Minimum Scan Engine: 9.850
FIRST VSAPI PATTERN FILE: 15.884.07
FIRST VSAPI PATTERN DATE: 17 May 2020
VSAPI OPR PATTERN File: 15.885.00
VSAPI OPR PATTERN Date: 18 May 2020

Step 1

Trend Micro Predictive Machine Learning detects and blocks malware at the first sign of its existence, before it executes on your system. When enabled, your Trend Micro product detects this malware under the following machine learning name:

     
    • Troj.Win32.TRX.XXPE50FFF035

Step 2

Before doing any scans, Windows 7, Windows 8, Windows 8.1, and Windows 10 users must disable System Restore to allow full scanning of their computers.

Step 3

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 4

Search and delete these files

[ Learn More ]
There may be some component 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.
  • %Public%\Documents\RGNR_{8 Characters based on Computer Name}.txt
  • {Encrypted Directory}\RGNR_{8 Characters based on Computer Name}.txt

Step 5

Scan your computer with your Trend Micro product to delete files detected as Ransom.Win32.RAGNAR.A. 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 the following Trend Micro Support pages for more information:

Step 6

Restore encrypted files from backup.


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