Analysis by: Ricardo III Valdez
ALIASES:

Trojan.GenericKD.66260501 (BITDEFENDER)

 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. It avoids encrypting files with the following file extensions.

  TECHNICAL DETAILS

File Size: 83,920 bytes
File Type: DLL
Memory Resident: No
Initial Samples Received Date: 06 Apr 2023
Payload: Displays message/message boxes, Collects system information

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.

Process Termination

This Ransomware terminates the following services if found on the affected system:

  • MsDtsServer100
  • MsDtsServer130
  • MSSQL
  • MSSQLFDLauncher
  • MSSQLSERVER
  • MSSQLServerADHelper100
  • MSSQLServerOLAPService
  • ReportServer
  • Samss
  • SQLAgent
  • SQLBrowser
  • SQLSERVERAGENT
  • SQLTELEMETRY
  • SQLWriter
  • SSISTELEMETRY130
  • Storflt
  • TMBMServer
  • UniFi
  • veeamcatalogsvc
  • veeamcloudsvc
  • veeamdeploysvc
  • vmicguestinterface
  • vmicheartbeat
  • vmickvpexchange
  • vmicrdv
  • vmicshutdown
  • vmictimesync
  • vmicvss

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

  • agntsvc.exe
  • dbeng50.exe
  • dbsnmp.exe
  • encsvc.exe
  • excel.exe
  • fdhost.exe
  • fdlauncher.exe
  • firefoxconfig.exe
  • infopath.exe
  • msaccess.exe
  • MsDtsSrvr.exe
  • msftesql.exe
  • msmdsrv.exe
  • mspub.exe
  • mydesctopservice.exe
  • mysql*
  • notepad*
  • ntdbsmgr.exe
  • ocautoupds.exe
  • ocomm.exe
  • ocssd.exe
  • onenote.exe
  • oracle*
  • outlook.exe
  • pg_*
  • postgres.exe
  • powerpnt.exe
  • ReportingServecesService.exe
  • ReportingServicesService.exe
  • sqbcoreservice.exe
  • sql*
  • Ssms.exe
  • synctime.exe
  • tbirdconfig.exe
  • thebat.exe
  • thebat64.exe
  • thunderbird.exe
  • UniFi.exe
  • veeam*
  • visio.exe
  • winword.exe
  • wordpad.exe

Information Theft

This Ransomware gathers the following data:

  • Processor Architecture
  • Native System Info
  • Number of Processors
  • Shadow Copy IDs

Other Details

This Ransomware requires the following additional components to properly run:

  • nclauncher.exe → loader, legitimate Network Connect Launcher executable
  • version.man→ encrypted binary, detected as Ransom.Win32.WANNAREN.D.enc
  • event.man→ encrypted binary, detected as Ransom.Win32.WANNAREN.D.enc

It does the following:

  • It checks for the existence of a "CONFIG" file:
    • If it exists,
      It uses the following settings:
      • Appended extension to encrypted files: .jstss
      • File name of Ransom note: READ ME.TXT
      • Ransom note contents: THIS IS TEST DECRYPT

    • If it doesn't exists,
      It proceeds with its malicious behaviors using the default settings

Ransomware Routine

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

  • autorun.inf
  • boot.ini
  • bootfont.bin
  • bootmgfw.efi
  • bootmgr
  • bootmgr.efi
  • bootsect.bak
  • desktop.ini
  • iconcache.db
  • ntldr
  • ntuser.dat
  • ntuser.dat.log
  • ntuser.ini
  • n241.helloadmin.txt

It avoids encrypting files found in the following folders:

  • #recycle
  • $Recycle.Bin
  • All Users
  • Boot
  • Google
  • Internet Explorer
  • Mozilla
  • Mozilla Firefox
  • Opera
  • Opera Software
  • Program Files
  • Program Files (x86)
  • ProgramData
  • Tor Browser
  • Windows
  • Windows.old
  • Folders with the following case sensitive strings:
    • remove
    • delete
    • Remove
    • Delete
    • REMOVE
    • DELETE

It appends the following extension to the file name of the encrypted files:

  • .scl

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

  • %Desktop%\n241.helloadmin.txt
  • {All Available Drives}\n241.helloadmin.txt

It avoids encrypting files with the following file extensions:

  • .exe
  • .dll
  • .sys
  • .bat
  • .msi
  • .scl

  SOLUTION

Minimum Scan Engine: 9.800
FIRST VSAPI PATTERN FILE: 18.354.03
FIRST VSAPI PATTERN DATE: 31 Mar 2023
VSAPI OPR PATTERN File: 18.355.00
VSAPI OPR PATTERN Date: 01 Apr 2023

Step 1

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 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

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.
  • %Desktop%\n241.helloadmin.txt
  • %Desktop%\READ ME.TXT
  • {All Available Drives}\n241.helloadmin.txt
  • {All Available Drives}\READ ME.TXT

Step 4

Scan your computer with your Trend Micro product to delete files detected as Ransom.Win32.WANNAREN.D. 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 5

Restore encrypted files from backup.


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