RANSOM_CERBER.BG

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 modifies the Internet Explorer Zone Settings.

It connects to certain websites to send and receive information.

It encrypts files with specific file extensions. It encrypts files found in specific folders.

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.

Autostart Technique

This Ransomware drops the following shortcut pointing to its copy in the User Startup folder to enable its automatic execution at every system startup:

• {malware name}.lnk

Other System Modifications

This Ransomware changes the desktop wallpaper by modifying the following registry entries:

HKEY_CURRENT_USER\Control Panel\Desktop
Wallpaper = "%TEMP%\tmp{random}.bmp"

It sets the system's desktop wallpaper to the following image:

Web Browser Home Page and Search Page Modification

This Ransomware modifies the Internet Explorer Zone Settings.

Dropping Routine

This Ransomware drops the following files:

• %Desktop%\_HOW_TO_DECRYPT_MY_FILES_{random characters}_.hta
• %Desktop%\_HOW_TO_DECRYPT_MY_FILES_{random characters}_.txt
• %TEMP%\{8 random characters}\{4 random characters}.tmp
• %TEMP%\tmp{random}.bmp
• {folder of encrypted files}\_HOW_TO_DECRYPT_MY_FILES_{random characters}_.hta

(Note: %Desktop% is the desktop folder, where it usually is C:\Documents and Settings\{user name}\Desktop in Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\Desktop in Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

Other Details

This Ransomware connects to the following website to send and receive information:

• 15.42.13.0/27:6893
• 44.66.140.0/27:6893
• 87.98.176.0/22:6893

It executes the following command to disable/stop/delete Windows components:

• %System%\netsh.exe advfirewall set allprofiles state on
• %System%\netsh.exe advfirewall reset

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

Ransomware Routine

This Ransomware encrypts files with the following extensions:

• .doc
• .docx
• .xls
• .xlsx
• .jpg
• .jpeg
• .pdf
• .rar
• .zip
• .ppt
• .pptx
• .avi
• .mpg
• .mpeg
• .wmv

It encrypts files found in the following folders:

• \bitcoin\
• \excel\
• \microsoft sql server\
• \microsoft\excel\
• \microsoft\microsoft sql server\
• \microsoft\office\
• \microsoft\onenote\
• \microsoft\outlook\
• \microsoft\powerpoint\
• \microsoft\word\
• \office\
• \onenote\
• \outlook\
• \powerpoint\
• \steam\
• \the bat!\
• \thunderbird\
• \word\

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

• bootsect.bak
• iconcache.db
• ntuser.dat
• thumbs.db

It avoids encrypting files with the following strings in their file path:

• :\$getcurrent\
• :\$recycle.bin\
• :\$windows.~bt\
• :\$windows.~ws\
• :\boot\
• :\documents and settings\all users\
• :\documents and settings\default user\
• :\documents and settings\localservice\
• :\documents and settings\networkservice\
• :\intel\
• :\logs\
• :\msocache\
• :\perflogs\
• :\program files (x86)\
• :\program files\
• :\programdata\
• :\recovery\
• :\recycled\
• :\recycler\
• :\system volume information\
• :\system.sav\
• :\temp\
• :\windows.old\
• :\windows10upgrade\
• :\windows\
• :\winnt\
• \appdata\local\
• \appdata\locallow\
• \appdata\roaming\
• \local settings\
• \public\music\sample music\
• \public\pictures\sample pictures\
• \public\videos\sample videos\
• \tor browser\

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

NOTES:
It avoids infecting system with the following OS language codes: