Ransom.Win64.ROOK.YXBLFZ

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 executes then deletes itself afterward.

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 adds the following processes:

• %System%\cmd.exe /c vssadmin.exe delete shadows /all /quiet

(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

It executes then deletes itself afterward.

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

• asfgjkl878645165456fa888

Other System Modifications

This Ransomware adds the following registry entries:

HKEY_CURRENT_USER\Software
RookPrivateKey = {Hex Values}

HKEY_CURRENT_USER\Software
RookPublicKey = {Hex Values}

Process Termination

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

• AcronisAgent
• AcrSch2Svc
• backup
• CAARCUpdateSvc
• CASAD2DWebSvc
• ccEvtMgr
• ccSetMgr
• DefWatch
• GxBlr
• GxCIMgr
• GxCVD
• GxFWD
• GxVss
• Intuit.QuickBooks.FCS
• memtas
• mepocs
• QBCFMonitorService
• QBFCService
• QBIDPService
• RTVscan
• SavRoam
• sql
• svc$
• torService
• veeam
• vss

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

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

Other Details

This Ransomware does the following:

• Deletes all files inside Recycle Bin
• Encrypts files from network shares
• Creates Semaphore

It accepts the following parameters:

• -debug - For logging
• -shares - Encrypts specified network shares
• -paths - Encrypts specified drives

Ransomware Routine

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

• #recycle
• $Recycle Bin
• All Users
• AppData
• autorun.inf
• Boot
• boot.ini
• bootfont.bin
• bootmgfw.efi
• bootmgr
• bootmgr.efi
• bootsect.bak
• desktop.ini
• Google
• iconcache.db
• Internet Explorer
• Mozilla
• Mozilla Firefox
• ntldr
• ntuser.dat
• ntuser.dat.log
• ntuser.ini.
• Opera
• Opera Software
• Program Files
• Program Files (x86)
• ProgramData
• thumbs.db
• Tor Browser
• Windows
• Windows.old
• HowToRestoreYourFiles.txt

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

• Rook

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

• {Encrypted Directory}\HowToRestoreYourFiles.txt
  

It avoids encrypting files with the following file extensions:

• .exe
• .dll
• .Rook