Ransom.Win32.CRYSIS.TIBGIF

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.

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 copies of itself into the affected system:

• %System%\{Malware Filename}.exe
• %Application Data%\{Malware Filename}.exe
• %User Startup%\{Malware FileName}.exe
• %Common Startup%\{Malware Name}.exe

(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.. %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).. %User Startup% is the current user's Startup folder, which is usually C:\Windows\Profiles\{user name}\Start Menu\Programs\Startup on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Start Menu\Programs\Startup on Windows NT, C:\Documents and Settings\{User name}\Start Menu\Programs\Startup on Windows 2003(32-bit), XP and 2000(32-bit), or C:\Users\{user name}\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit), 10(64-bit).. %Common Startup% is the startup folder for all users, which is usually C:\Documents and Settings\All Users\Start Menu\Programs\Startup on Windows 2000, XP, and Server 2003, or C:\ProgramData\Microsoft\Windows\Start Menu\Programs\Startup on Windows Vista, 7, and 8.)

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

• Global\syncronize_X2R0E9A
• Global\syncronize_X2R0E9U

Autostart Technique

This Ransomware adds the following registry entries to enable its automatic execution at every system startup:

HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows\CurrentVersion\Run
{Malware FileName} = %System%\{Malware FileName}

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{Malware FileName} = %Application Data%\{Malware FileName}

Other System Modifications

This Ransomware adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
%Application Data%\Info.hta = mshta.exe "%Application Data%\Info.hta"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
%System%\Info.hta = mshta.exe "%System%\Info.hta"

Process Termination

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

• 1c8.exe
• 1cv77.exe
• outlook.exe
• postgres.exe
• mysqld-nt.exe
• mysqld.exe
• sqlservr.exe
• FirebirdGuardianDefaultInstance
• FirebirdServerDefaultinstance
• sqlwriter
• mssqlserver
• sqlserveradhelper

Other Details

This Ransomware does the following:

• Delete shadow copies by executing the following command in CMD: "vssadmin delete shadows /all /quiet"
• Uses CMD to execute: "mode con cp select=1251"
• It is capable of encrypting files in all fixed, remote and removable drives.
• Displays the ransom note Info.hta as a payload after encrypting files.

Ransomware Routine

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

• boot.ini
• bootfont.bin
• ntldr
• ntdetect.com
• io.sys
• FILES ENCRYPTED.txt
• Info.hta
• {Malware Filename}.exe

It avoids encrypting files found in the following folders:

• %Windows%

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

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

• id-{ID}.[b{BLOCKED}1@foxmail.com ].harma

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

• %System%\Info.hta
• %Application Data%\Info.hta
• %Common Startup%\Info.hta
• %User Startup%\Info.hta
• 

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

• %Desktop%\FILES ENCRYPTED.txt
• {Encrypted Directory}\FILES ENCRYPTED.txt
•