Ransom.MSIL.WANNASCREAM.B

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 connects to certain websites to send and receive information.

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 adds the following processes:

• %System%\mshta.exe "%User Startup%\info.hta"

(Note: %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).)

Autostart Technique

This Ransomware drops the following file(s) in the Windows User Startup folder to enable its automatic execution at every system startup:

• %User Startup%\Runtime Broker.exe -> copy of itself
• %User Startup%\info.hta -> contains ransom note

(Note: %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).)

Information Theft

This Ransomware gathers the following data:

• Operating System
• CPU information
• Public IP Address
• Total Size of All Logical Drives
• Machine Name
• Volume Serial Number
• Processor ID

Other Details

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

• http://recoverydata.{BLOCKED}sting.com/db

It encrypts files with the following extensions:

• .exe
• .der
• .pfx
• .key
• .crt
• .dat
• .nfo
• .bmp
• .ini
• .csr
• .p12
• .pem
• .odt
• .sxw
• .stw
• .3ds
• .max
• .3dm
• .ods
• .sxc
• .stc
• .dif
• .slk
• .wb2
• .odp
• .sxd
• .std
• .sxm
• .sqlite3
• .sqlitedb
• .sql
• .accdb.mdb
• .dbf
• .odb
• .mdf
• .ldf
• .cpp
• .pas
• .asm
• .cmd
• .bat
• .vbs
• .sch
• .jsp
• .php
• .asp
• .java
• .jar
• .class
• .mp3
• .wav
• .swf
• .fla
• .wmv
• .mpg
• .vob
• .mpeg
• .asf
• .avi
• .mov
• .mp4
• .mkv
• .flv
• .wma
• .mid
• .m3u
• .m4u.svg
• .psd
• .tiff
• .tif
• .raw
• .gif
• .png
• .bmp
• .jpg
• .jpeg
• .iso
• .backup
• .zip
• .rar
• .tgz
• .tar
• .bak
• .ARC
• .vmdk
• .vdi
• .sldm
• .sldx
• .sti
• .sxi
• .dwg
• .pdf
• .wk1
• .wks
• .rtf
• .csv
• .txt
• .msg
• .pst
• .ppsx
• .ppsm.pps
• .pot
• .pptm
• .pptx
• .ppt
• .xltm
• .xltx
• .xlc
• .xlm
• .xlt
• .xlw
• .xlsb
• .xlsm
• .xlsx
• .xls
• .dotm
• .dot
• .docm
• .docx
• .doc
• .ndf
• .pdf
• .ib
• .ibk.1cd
• .3dm
• .3ds
• .3fr
• .3g2
• .3gp
• .3pr.7z
• .7zip.avhdx
• .aac
• .aaf
• .ab4
• .accdb
• .accde
• .accdr
• .accdt
• .ach
• .acr
• .act
• .adb
• .adp
• .ads
• .aep
• .aepx
• .aes
• .aet
• .agdl
• .ai
• .aif
• .aiff
• .ait
• .al
• .amr
• .aoi
• .apj
• .apk
• .arch00
• .arw
• .as
• .as3
• .asf
• .asm
• .asp
• .aspx
• .asset
• .asx
• .atr
• .avi
• .awg.back
• .backup
• .backupdb
• .bak
• .bar
• .bay
• .bc6
• .bc7
• .bdb
• .bgt
• .big
• .bik
• .bin
• .bkf
• .bkp
• .blend
• .blob
• .bmd
• .bmp
• .bpw
• .bsa.c
• .cas
• .cdc
• .cdf
• .cdr
• .cdr3
• .cdr4
• .cdr5
• .cdr6
• .cdrw
• .cdx
• .ce1
• .ce2
• .cer
• .cfg
• .cfr
• .cgm
• .cib
• .class
• .cls
• .cmt
• .config
• .contact
• .cpi
• .cpp
• .cr2
• .craw
• .crt
• .crw
• .cs
• .csh
• .csl
• .css
• .csv.d3dbsp
• .dac
• .dar
• .das
• .dat
• .dazip
• .db
• .db0
• .db3
• .dba
• .dbf
• .dbx
• .db_journal
• .dc2
• .dcr
• .dcs
• .ddd
• .ddoc
• .ddrw
• .dds
• .der
• .des
• .desc
• .design
• .dgc
• .dir
• .dit
• .djvu
• .dmp
• .dng
• .doc
• .docb
• .docm
• .docx
• .dot
• .dotm
• .dotx
• .drf
• .drw
• .dtd
• .dwg
• .dxb
• .dxf
• .dxg.dll.easm
• .edb
• .efx
• .eml
• .epk
• .eps
• .erbsql
• .erf
• .esm
• .exf.fdb
• .ff
• .ffd
• .fff
• .fh
• .fhd
• .fla
• .flac
• .flf
• .flv
• .flvv
• .forge
• .fos
• .fpk
• .fpx
• .fsh
• .fxg
• .gdb
• .gdoc
• .gho
• .gif.gmap
• .gray
• .grey
• .groups
• .gry
• .gsheet.h
• .hbk
• .hdd
• .hkdb
• .hkx
• .hplg
• .hpp
• .htm
• .html
• .hvpl.ibank
• .ibd
• .ibz
• .icxs
• .idml
• .idx
• .iff
• .iif
• .iiq
• .incpas
• .indb
• .indd
• .indl
• .indt
• .inx
• .itdb
• .itl
• .itm
• .iwd
• .iwi.jar
• .java
• .jnt
• .jpe
• .jpeg
• .jpg.js
• .kc2
• .kdb
• .kdbx
• .kdc
• .key
• .kf
• .kpdx
• .kwm.laccdb
• .layout
• .lbf
• .lck
• .ldf
• .lit
• .litemod
• .log
• .lrf
• .ltx
• .lua
• .lvl.m
• .m2
• .m2ts
• .m3u
• .m3u8
• .m4a
• .m4p
• .m4u
• .m4v
• .map
• .max
• .mbx
• .mcmeta
• .md
• .mdb
• .mdbackup
• .mdc
• .mddata
• .mdf
• .mdi
• .mef
• .menu
• .mfw
• .mid
• .mkv
• .mlb
• .mlx
• .mmw
• .mny
• .mos
• .mov
• .mp3
• .mp4
• .mpa
• .mpeg
• .mpg
• .mpp
• .mpqge
• .mrw
• .mrwref
• .msg
• .myd.nc
• .ncf
• .nd
• .ndd
• .ndf
• .nef
• .nk2
• .nop
• .nrw
• .ns2
• .ns3
• .ns4
• .nsd
• .nsf
• .nsg
• .nsh
• .ntl
• .nvram
• .nwb
• .nx2
• .nxl
• .nyf.oab
• .obj
• .odb
• .odc
• .odf
• .odg
• .odm
• .odp
• .ods
• .odt
• .ogg
• .oil
• .orf
• .ost
• .otg
• .oth
• .otp
• .ots
• .ott.p12
• .p7b
• .p7c
• .pab
• .pages
• .pak
• .pas
• .pat
• .pcd
• .pct
• .pdb
• .pdd
• .pdf
• .pef
• .pem
• .pfx
• .php
• .pif
• .pkpass
• .pl
• .plb
• .plc
• .plt
• .plus_muhd
• .pmd
• .png
• .po
• .pot
• .potm
• .potx
• .ppam
• .ppj
• .ppk
• .pps
• .ppsm
• .ppsx
• .ppt
• .pptm
• .pptx
• .prel
• .prf
• .prproj
• .ps
• .psafe3
• .psd
• .psk
• .pst
• .ptx
• .pwm
• .py.qba
• .qbb
• .qbm
• .qbr
• .qbw
• .qbx
• .qby
• .qcow
• .qcow2
• .qdf
• .qed
• .qic.r3d
• .ra
• .raf
• .rar
• .rat
• .raw
• .rb
• .rdb
• .re4
• .rgss3a
• .rim
• .rm
• .rofl
• .rtf
• .rvt
• .rw2
• .rwl
• .rwz.s3db
• .srt
• .safe
• .sas7bdat
• .sav
• .save
• .say
• .sb
• .sd0
• .sda
• .sdf
• .ses
• .shx
• .sid
• .sidd
• .sidn
• .sie
• .sis
• .sldasm
• .sldblk
• .sldm
• .sldprt
• .sldx
• .slm
• .snx
• .sql
• .sqlite
• .sqlite3
• .sqlitedb
• .sr2
• .srf
• .srt
• .srw
• .st4
• .st5
• .st6
• .st7
• .st8
• .stc
• .std
• .sti
• .stl
• .stm
• .stw
• .stx
• .sum
• .svg
• .swf
• .sxc
• .sxd
• .sxg
• .sxi
• .sxm
• .sxw
• .syncdb.t12
• .t13
• .tap
• .tax
• .tex
• .tga
• .thm
• .tif
• .tlg
• .tor
• .txt.upk.v3d
• .vbox
• .vcf
• .vdf
• .vdi
• .vfs0
• .vhd
• .vhdx
• .vmdk
• .vmsd
• .vmx
• .vmxf
• .vob
• .vpk
• .vpp_pc
• .vtf
• .VMRS.w3x
• .wab
• .wad
• .wallet
• .wav
• .vmcx
• .wb2
• .wma
• .wmo
• .wmv
• .wotreplay
• .wpd
• .wps.x11
• .x3f
• .xf
• .xis
• .xla
• .xlam
• .xlk
• .xll
• .xlm
• .xlr
• .xls
• .xlsb
• .xlsb3dm
• .xlsm
• .xlsx
• .xlt
• .xltm
• .xltx
• .xlw
• .xml
• .xqx
• .xxx.ycbcra
• .yuv
• .zip
• .ztmp

Ransomware Routine

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

• %User Startup%\info.hta
• %User Startup%\Runtime Broker.exe

(Note: %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).)

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

• C:\BOOTNXT
• C:\bootmgr
• C:\boot.sdi
• C:\BOOTSECT.BAK
• C:\Windows
• C:\Windows.old
• C:\Boot
• C:\Windows10Upgrade
• C:\$Recycle.Bin
• C:\$Windows.~WS
• C:\Program Files (x86)
• C:\Program Files
• A:\

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

• [Darkcrypt91@protonmail.com][UID].lock

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

• {infected directory path}\ReadMe.txt

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

• %User Startup%\info.hta
  
• {infected directory path}\ReadMe.txt