Ransom.Win32.BRAINCIPHER.THGAEBD

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.

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:

• %ProgramData%\{Random}.tmp → used to delete the malware, deleted afterwards

(Note: %ProgramData% is a version of the Program Files folder where any user on a multi-user computer can make changes to programs. This contains application data for all users. This is usually C:\ProgramData on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit), or C:\Documents and Settings\All Users on Windows Server 2003(32-bit), 2000(32-bit) and XP.)

It adds the following processes:

• %ProgramData%\{Random}.tmp
• "%System%\cmd.exe" /C DEL /F /Q %ProgramData%\{Random}.tmp >> NUL

(Note: %ProgramData% is a version of the Program Files folder where any user on a multi-user computer can make changes to programs. This contains application data for all users. This is usually C:\ProgramData on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit), or C:\Documents and Settings\All Users on Windows Server 2003(32-bit), 2000(32-bit) and XP.. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

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

• Global\{Generated Hash}

Process Termination

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

• securityhealthservice
• sense
• sppsvc
• wdboot
• wdfilter
• wdnisdrv
• wdnissvc
• windefend
• wscsvc
• vmicvss
• vss

Other Details

This Ransomware does the following:

• It encrypts fixed, removable and network shares
• It deletes the following services:
  • securityhealthservice
  • sense
  • sppsvc
  • wdboot
  • wdfilter
  • wdnisdrv
  • wdnissvc
  • windefend
  • wscsvc
  • vmicvss
  • vss
• It deletes files in recycle bin folder for removable and fixed drives

It accepts the following parameters:

• -safe →Reboots in safeboot, then encrypts the user's machine
• -wall → Print ransom note on printers then deletes itself after renaming for 26 times.
• -path {target} → Specifically encrypt the target, can be file or folder
• -del → Deletes itself after renaming for 26 times.

Ransomware Routine

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

• autorun.inf
• boot.ini
• bootfont.bin
• bootsect.bak
• d3d9caps.dat
• desktop.ini
• GDIPFONTCACHEV1.DAT
• iconcache.db
• ntldr
• ntuser.dat
• ntuser.dat.log
• ntuser.ini
• thumbs.db

It avoids encrypting files found in the following folders:

• $recycle.bin
• $windows.~bt
• $windows.~ws
• all users
• boot
• config.msi
• default
• intel
• microsoft
• msocache
• perflogs
• program files
• program files (x86)
• programdata
• public
• system volume information
• tor browser
• windows
• windows.old
• x64dbg

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

• {7 Random Alphanumeric Characters}.sYMY1N6ah

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

• {Encrypted Directory}\sYMY1N6ah.README.txt
  

It avoids encrypting files with the following file extensions:

• 386
• adv
• ani
• bat
• bin
• cab
• cmd
• com
• cpl
• cur
• deskthemepack
• diagcab
• diagcfg
• diagpkg
• dll
• drv
• exe
• hlp
• hta
• icl
• icns
• ico
• ics
• idx
• key
• ldf
• lnk
• lock
• mod
• mpa
• msc
• msi
• msp
• msstyles
• msu
• nls
• nomedia
• ocx
• pdb
• prf
• ps1
• rom
• rtp
• scr
• search-ms
• shs
• spl
• sys
• theme
• themepack
• wpx