Win32/Filecoder.LockedFile [Threat Name] go to Threat

Win32/Filecoder.LockedFile.I [Threat Variant Name]

Category	trojan
Size	1242112 B
Aliases	Ransom:Win32/GandCrab!bit (Microsoft)
	Trojan.Encoder.26420 (Dr.Web)
	W32/Ransom.ACK (F-Prot)

Short description

Win32/Filecoder.LockedFile.I is a trojan that encrypts files on fixed and network drives. To decrypt files the user is requested to comply with given conditions in exchange for a password/instructions.

Installation

When executed, the trojan copies itself into the following location:

%malwarefolder%\NW[%variable%].exe

A string with variable content is used instead of %variable% .

This copy of the trojan is then executed.

Payload information

Win32/Filecoder.LockedFile.I is a trojan that encrypts files on fixed and network drives.

The trojan searches for files with the following file extensions:

*.7Z
*.ACCDB
*.BAK
*.CDR
*.CELL
*.DB
*.DB2
*.DB3
*.DBC
*.DBF
*.DBK
*.DBS
*.DBS
*.DBX
*.DOC
*.DOCX
*.DOT
*.DOTX
*.DT
*.DWG
*.EQL
*.GZ
*.HCDT
*.HML
*.HPT
*.HSDT
*.HWDT
*.HWP
*.HWPX
*.HWT
*.JPEG
*.JPG
*.LDF
*.MDB
*.MDF
*.MYD
*.NDF
*.NDF
*.NS2
*.NS3
*.NS4
*.NSF
*.NXL
*.NXT
*.ODS
*.ODT
*.PDF
*.PSD
*.RAR
*.SDF
*.SHOW
*.SQL
*.SQLITE
*.SQLITE3
*.SQLITEDB
*.TAR
*.TIB
*.VHD
*.VPD
*.XLS
*.XLSX
*.ZIP

It avoids files with the following extensions:

*.BLF
*.BMP
*.DLL
*.ICO
*.LOG
*.LOG1
*.LOG2
*.RBS
*.RDP
*.REGTRANS-MS
*.RTF
*.SEARCH-MS
*.SEK
*.SETTINGCONTENT-MS
*.TMP
*.VBS
*.XML

It avoids files which contain any of the following strings in their path:

(X86)\ACRONIS\
(X86)\BACKUP MANAGER\
(X86)\BACKUPCLIENT\
(X86)\CARBONITE\
(X86)\DROPBOX\
(X86)\GOOGLE\DRIVE\
(X86)\MICROSOFT ONEDRIVE\
(X86)\ONEDRIVE\
\$RECYCLE.BIN\
\7-ZIP\
\ASPNET_CLIENT\
\AVAST
\AVDEFENDER
\AVG
\BITDEFENDER
\BOOT\
\COMMON FILES\
\DEFAULT USER\
\DVD MAKER\
\ESET
\INTERNET EXPLORER\
\KASPERSKY LAB
\KASPERSKYLAB
\MALWAREBYTES
\MCAFEE
\MICROSOFT OFFICE\
\MICROSOFT SILVERLIGHT\
\MICROSOFT\CRYPTO\
\MICROSOFT\OFFICE\
\MICROSOFT\PROVISIONING\
\MSOCACHE\
\PANDA SECURITY
\PROGRAMDATA\MICROSOFT\
\REFERENCE ASSEMBLIES\
\SOPHOS
\SYMANTEC ENDPOINT
\TEMP\
\TOR BROWSER\
\TREND MICRO
\WINDOWS DEFENDER\
\WINDOWS MEDIA PLAYER\
\WINDOWS NT\
\WINDOWS SIDEBAR\
\WINDOWS.OLD\
\WINDOWS\
\WINDOWS10UPGRADE\
\WINDOWSAPPS\
\WINDOWSPOWERSHELL\
\WINRAR\
FILES\ACRONIS\
FILES\BACKUP MANAGER\
FILES\BACKUPCLIENT\
FILES\CARBONITE\
FILES\DROPBOX\
FILES\GOOGLE\DRIVE\
FILES\MICROSOFT ONEDRIVE\
FILES\ONEDRIVE\

The trojan encrypts the file content.

The RSA, ChaCha20 encryption algorithm is used.

The name of the encrypted file is changed to:

[ransomriggs@qq.com].%randomstring1%-%randomstring2%.EMAN50

A string with variable content is used instead of %randomstring1-2% .

To decrypt files the user is requested to comply with given conditions in exchange for a password/instructions.

When searching the drives, the trojan creates the following file in every folder visited:

#README_EMAN50#.rtf

It contains the following text:

HOW TO RECOVER YOUR FILES INSTRUCTION ATENTION!!! We are realy sorry to inform you that ALL YOUR FILES WERE ENCRYPTED by our automatic software. It became possible because of bad server security. ATENTION!!! Please don't worry, we can help you to RESTORE your server to original state and decrypt all your files quickly and safely! INFORMATION!!! Files are not broken!!! Files were encrypted with AES-128+RSA-2048 crypto algorithms. There is no way to decrypt your files without unique decryption key and special software. Your unique decryption key is securely stored on our server. For our safety, all information about your server and your decryption key will be automaticaly DELETED AFTER 7 DAYS! You will irrevocably lose all your data! * Please note that all the attempts to recover your files by yourself or using third party tools will result only in irrevocable loss of your data! * Please note that you can recover files only with your unique decryption key, which stored on our side. If you will use the help of third parties, you will only add a middleman. HOW TO RECOVER FILES??? Please write us to the e-mail (write on English or use professional translator): ransomriggs@qq.com ransomriggs@protonmail.com ransomriggs@tutanota.com You have to send your message on each of our 3 emails due to the fact that the message may not reach their intended recipient for a variety of reasons! In subject line write your personal ID: ############### We recommed you to attach 3 encrypted files to your message. We will demonstrate that we can recover your files. * Please note that files must not contain any valuable information and their total size must be less than 5Mb. OUR ADVICE!!! Please be sure that we will find common languge. We will restore all the data and give you recommedations how to configure the protection of your server. We will definitely reach an agreement ;) !!! ALTERNATIVE COMMUNICATION If yоu did nоt rеcеivе thе аnswеr frоm thе аfоrеcitеd еmаils fоr mоrе then 24 hours please sеnd us Bitmеssаgеs frоm а wеb brоwsеr thrоugh thе wеbpаgе https://bitmsg.me. Bеlоw is а tutоriаl оn hоw tо sеnd bitmеssаgе viа wеb brоwsеr: 1. Оpеn in yоur brоwsеr thе link https://bitmsg.me/users/sign_up аnd mаkе thе rеgistrаtiоn bу еntеring nаmе еmаil аnd pаsswоrd. 2. Уоu must cоnfirm thе rеgistrаtiоn, rеturn tо уоur еmаil аnd fоllоw thе instructiоns thаt wеrе sеnt tо уоu. 3. Rеturn tо sitе аnd сlick "Lоgin" lаbеl оr usе link https://bitmsg.me/users/sign_in, еntеr уоur еmаil аnd pаsswоrd аnd click thе "Sign in" buttоn. 4. Сlick thе "Сrеаtе Rаndоm аddrеss" buttоn. 5. Сlick thе "Nеw mаssаgе" buttоn. 6. Sеnding mеssаgе: Tо: Еntеr аddrеss: empty Subjесt: Еntеr уоur ID: ############### Mеssаgе: Dеscribе whаt уоu think nеcеssаrу. Сlick thе "Sеnd mеssаgе" buttоn.

Information stealing

Win32/Filecoder.LockedFile.I is a trojan that steals sensitive information.

The trojan collects the following information:

malware version
computer name
user name

The trojan attempts to send gathered information to a remote machine.

The trojan contains a URL address. The HTTP protocol is used in the communication.

Other information

The trojan creates the following file:

%userdata%\%variable%.bmp

A string with variable content is used instead of %variable% .

This file/image is set as a wallpaper.

The following Registry entries are set:

[HKEY_CURRENT_USER\Control Panel\Desktop]
- "Wallpaper" = "%userdata%\%variable%.bmp"
- "WallpaperStyle" = 0
- "TileWallpaper" = 0

The trojan creates the following files:

%malwarefolder%\ALL_dmp.fldp
%malwarefolder%\log.txt
%malwarefolder%\LFIN_%id%.txt

A string with variable content is used instead of %id% .