Ransom.Win32.LOCKBIT.YXECF

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

Detalles de entrada

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

Instalación

Infiltra los archivos siguientes:

• %ProgramData%\4adERwmcM.ico → icon of encrypted files
• %ProgramData%\4adERwmcM.bmp → desktop wallpaper after encryption

Agrega los procesos siguientes:

• bcdedit /set {current} safeboot network → if -safe commandline parameter is used.

Agrega las siguientes exclusiones mutuas para garantizar que solo se ejecuta una de sus copias en todo momento:

• Global\{generated hash}

Otras modificaciones del sistema

Agrega las siguientes entradas de registro:

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
.4adERwmcM
{Default} = 4adERwmcM

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
4adERwmcM\DefaultIcon
{Default} = C:\ProgramData\4adERwmcM.ico

Cambia el fondo de escritorio mediante la modificación de las siguientes entradas de registro:

HKEY_CURRENT_USER\Control Panel\Desktop
Wallpaper = %ProgramData%\4adERwmcM.bmp

HKEY_CURRENT_USER\Control Panel\Desktop
WallpaperStyle = 10

Este malware establece la imagen siguiente como fondo de escritorio del sistema:

Finalización del proceso

Finaliza los servicios siguientes si los detecta en el sistema afectado:

• vss
• sql
• svc$
• memtas
• mepocs
• msexchange
• sophos
• veeam
• backup
• GxVss
• GxBlr
• GxFWD
• GxCVD
• GxCIMgr

Finaliza los procesos siguientes si detecta que se ejecutan en la memoria del sistema afectado:

• sql
• oracle
• ocssd
• dbsnmp
• synctime
• agntsvc
• synctime
• isqlplussvc
• xfssvccon
• mydesktopservice
• ocautonupds
• encsvc
• firefox
• tbirdconfig
• mydesktopqos
• ocomm
• dbeng50
• sqbcoreservice
• excel
• infopath
• msaccess
• mspub
• onenote
• outlook
• powerpnt
• steam
• thebat
• thunderbird
• visio winword
• wordpad
• notepad

Robo de información

Recopila los siguientes datos:

• Hostname
• Username
• OS version
• Domain
• Architecture
• Language

Otros detalles

Agrega las siguientes entradas de registro como parte de la rutina de instalación:

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
.4adERwmcM

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
4adERwmcM\DefaultIcon

Hace lo siguiente:

• If not executed with admin rights, it will attempt to relaunch itself as admin by elevating its privileges via bypassing UAC
• It encrypts fixed, removable and network shares
• It deletes files in recycle bin folder for removable and fixed drives
• It uses WQL to delete shadow copies
• It renames itself 26 times before deleting itself after encryption
• It has the capability to print the ransom note in infected machines
• It terminates if the machine has the following system language:
  • Arabic (Syria)
  • Armenian (Armenia)
  • Azerbaijani (Cyrillic Azerbaijan)
  • Azerbaijani (Latin Azerbaijan)
  • Belarusian (Belarus)
  • Georgian (Georgia)
  • Kazakh (Kazakhstan)
  • Kyrgyz (Kyrgyzstan)
  • Russian (Moldova)
  • Russian (Russia)
  • Tajik (Cyrillic Tajikistan)
  • Tatar (Russia)
  • Romanian (Moldova)
  • Turkmen (Turkmenistan)
  • Ukranian (Ukraine)
  • Uzbek (Cyrillic Uzbekistan)
  • Uzbek (Latin Uzbekistan)
• It deletes the following services:
  • WdBoot
  • WdFilter
  • WdNisDrv
  • WdNisSvc
  • WinDefend
  • wscsvc
  • sppsvc
  • Sense
  • SecurityHealthService
• It changes the encrypted file icon to the following image:
  
  
• It duplicates the token of the following:
  • explorer.exe - to gain privileged domain access
  • lsass.exe
  • TrustedInstaller - service is started if not yet running
• It contains a list of username:password that it will use to log into domain controllers.