TROJ_CRYPWALL.XXRK

This Trojan modifies registry entries to disable various system services. This action prevents most of the system functions to be used.

It connects to certain websites to send and receive information. It deletes the initially executed copy of itself.

Installation

This Trojan drops the following copies of itself into the affected system:

• %System Root%\{random 8 characters}\{random 8 characters}.exe
• %Application Data%\{random 8 characters}.exe
• %User Startup%\{random 8 characters}.exe

(Note: %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.. %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on 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.. %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, and C:\Documents and Settings\{User name}\Start Menu\Programs\Startup.)

It drops the following files:

• %User Startup%\HELP_DECRYPT.HTML
• %User Startup%\HELP_DECRYPT.PNG
• %User Startup%\HELP_DECRYPT.TXT
• %User Startup%\HELP_DECRYPT.URL

(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, and C:\Documents and Settings\{User name}\Start Menu\Programs\Startup.)

It drops and executes the following files:

• %Desktop%\HELP_DECRYPT.HTML
• %Desktop%\HELP_DECRYPT.PNG
• %Desktop%\HELP_DECRYPT.TXT
• %Desktop%\HELP_DECRYPT.URL

(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.)

It adds the following processes:

• explorer.exe
• svchost.exe

It is injected into the following processes running in memory:

• created explorer.exe
• created svchost.exe

Autostart Technique

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\RunOnce
*{random 6 characters} = "%System Root%\{random 8 characters}\{random 8 characters}.exe" (for Windows Vista and above only)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\RunOnce
*{random 7 characters} = "%Application Data%\{random 8 characters}.exe" (for Windows Vista and above only)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{random 7 characters} = "%System Root%\{random 8 characters}\{random 8 characters}.exe"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{random 8 characters} = "%Application Data%\{random 8 characters}.exe"

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

• %User Startup%\{random 8 characters}.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, and C:\Documents and Settings\{User name}\Start Menu\Programs\Startup.)

Other System Modifications

This Trojan adds the following registry keys:

HKEY_CURRENT_USER\Software\{UID}

HKEY_CURRENT_USER\Software\{UID}\
{random key}

It adds the following registry entries:

HKEY_CURRENT_USER\Software\{UID}
{random 2 characters} = "{contents of HELP_DECRYPT.URL}"

HKEY_CURRENT_USER\Software\{UID}
{random 2 characters} = "{contents of HELP_DECRYPT.TXT}"

HKEY_CURRENT_USER\Software\{UID}
{random 2 characters} = "{contents of HELP_DECRYPT.HTML}"

HKEY_CURRENT_USER\Software\{UID}
{random 2 characters} = "{RSA PUBLIC KEY}"

HKEY_CURRENT_USER\Software\{UID}\
{random key}
{Path and file of encrypted file} = "{hex values}"

It modifies the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\SystemRestore
DisableSR = "1"

(Note: The default value data of the said registry entry is 0.)

It modifies registry entries to disable the following system services:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\BITS
Start = "4"

(Note: The default value data of the said registry entry is 2.)

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\wscsvc
Start = "4"

(Note: The default value data of the said registry entry is 2.)

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ERSvc
Start = "4"

(Note: The default value data of the said registry entry is 2.)

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\wuauserv
Start = "4"

(Note: The default value data of the said registry entry is 2.)

Other Details

This Trojan connects to the following URL(s) to get the affected system's IP address:

• http://ip-addr.es
• http://myexternalip.com/raw
• http://curlmyip.com

It connects to the following website to send and receive information:

• {BLOCKED}hanyapi.com/wp-content/themes/pindol/g5.php
• {BLOCKED}hall.jimmyandpana.com/wp-content/plugins/w3-total-cache/lib/Microsoft/WindowsAzure/Storage/Blob/g4.php
• {BLOCKED}lyparent.com/wp-content/themes/quasartheme/g3.php
• {BLOCKED}eo.com/wp-content/themes/bretheon/g2.php
• {BLOCKED}irclelounge.com/wp-content/themes/striking_r/g1.php
• {BLOCKED}60newbuild.co.uk/wp-content/themes/Avada-Child-Theme/g5.php
• {BLOCKED}iverclub.ru/wp-content/themes/ingrid/g4.php
• {BLOCKED}ico.uk.com/wp-content/themes/whisper/g3.php
• {BLOCKED}4u.be/wp-content/themes/inovado/g2.php
• {BLOCKED}lenamann.com/wp-content/themes/the-bootstrap/g1.php
• {BLOCKED}dekorasyon.com.tr/wp-content/themes/webdesignV-5/g5.php
• {BLOCKED}osilbr.com.br/wp-content/themes/tecnosilbr/g4.php
• {BLOCKED}encia.es/wp-content/themes/CasualHotel/g3.php
• {BLOCKED}ta.com.br/wp-content/themes/pinpoint/g1.php
• {BLOCKED}ivalartesano.com/wp-content/themes/Avada/g5.php
• {BLOCKED}chitects.net/wp-content/themes/dkarchitects/g4.php
• {BLOCKED}heating.sk/wp-content/themes/tsk-theme/g3.php
• {BLOCKED}part.com/ueditor/dialogs/attachment/fileTypeImages/g2.php
• {BLOCKED}y-avt.com/wp-content/themes/nerey2/g1.php
• {BLOCKED}nix.com/wp-content/themes/attitude-pro/g5.php
• {BLOCKED}ectromenagers.ca/wp-content/themes/cheope/g4.php
• {BLOCKED}esestegemann.com/wp-content/themes/bostan/g3.php
• {BLOCKED}raddicted.com/SimplePhpTest001.php
• {BLOCKED}coskun.com/wp-content/themes/lotus/g1.php
• {BLOCKED}ukwerkend.be/wp-content/themes/ventus/g5.php
• {BLOCKED}tech.at/wp-content/themes/Avada/g4.php
• {BLOCKED}as.com.br/wp-content/uploads/revslider/drive_slider1/g3.php
• {BLOCKED}tstudio.com/wp-content/themes/contrast/g2.php
• {BLOCKED}ncansonax.com/wp-content/themes/kallyas/g1.php
• {BLOCKED}edunyasi.com/wp-content/themes/decoy/g2.php
• {BLOCKED}ll.stam.is/cache/Smarty/compile/g1.php
• {BLOCKED}uhendislik.com/wp-content/themes/rttheme17/g5.php
• {BLOCKED}niocassis.com.br/wp-content/themes/winestore/g4.php
• {BLOCKED}a-brugge.com/wp-content/themes/Avada/g3.php
• {BLOCKED}deira.com.br/wp-content/themes/Avada/g2.php
• {BLOCKED}i.nebevihayatyayinlari.com/wp-content/themes/Avada/g1.php

It encrypts files with the following extensions:

• 3dm
• 3ds
• 3fr
• 3g2
• 3gp
• 3pr
• 7z
• ab4
• accdb
• accde
• accdr
• accdt
• ach
• acr
• act
• adb
• ads
• agdl
• ai
• ait
• al
• apj
• arw
• asf
• asm
• asp
• asx
• avi
• awg
• back
• backup
• backupdb
• bak
• bank
• bay
• bdb
• bgt
• bik
• bkp
• blend
• bpw
• c
• cdf
• cdr
• cdr3
• cdr4
• cdr5
• cdr6
• cdrw
• cdx
• ce1
• ce2
• cer
• cfp
• cgm
• cib
• class
• cls
• cmt
• cpi
• cpp
• cr2
• craw
• crt
• crw
• cs
• csh
• csl
• csv
• dac
• db
• db3
• dbf
• db-journal
• dc2
• dcr
• dcs
• ddd
• ddoc
• ddrw
• dds
• der
• des
• design
• dgc
• djvu
• dng
• doc
• docm
• docx
• dot
• dotm
• dotx
• drf
• drw
• dtd
• dwg
• dxb
• dxf
• dxg
• eml
• eps
• erbsql
• erf
• exf
• fdb
• ffd
• fff
• fh
• fhd
• fla
• flac
• flv
• fpx
• fxg
• gray
• grey
• gry
• h
• hbk
• hpp
• ibank
• ibd
• ibz
• idx
• iif
• iiq
• incpas
• indd
• java
• jpe
• jpeg
• jpg
• kc2
• kdbx
• kdc
• key
• kpdx
• lua
• m
• m4v
• max
• mdb
• mdc
• mdf
• mef
• mfw
• mmw
• moneywell
• mos
• mov
• mp3
• mp4
• mpg
• mrw
• msg
• myd
• nd
• ndd
• nef
• nk2
• nop
• nrw
• ns2
• ns3
• ns4
• nsd
• nsf
• nsg
• nsh
• nwb
• nx2
• nxl
• nyf
• oab
• obj
• odb
• odc
• odf
• odg
• odm
• odp
• ods
• odt
• oil
• orf
• ost
• otg
• oth
• otp
• ots
• ott
• p12
• p7b
• p7c
• pab
• pages
• pas
• pat
• pcd
• pct
• pdb
• pdd
• pdf
• pef
• pem
• pfx
• php
• pl
• plc
• pot
• potm
• potx
• ppam
• pps
• ppsm
• ppsx
• ppt
• pptm
• pptx
• prf
• ps
• psafe3
• psd
• pspimage
• pst
• ptx
• py
• qba
• qbb
• qbm
• qbr
• qbw
• qbx
• qby
• r3d
• raf
• rar
• rat
• raw
• rdb
• rm
• rtf
• rw2
• rwl
• rwz
• s3db
• sas7bdat
• say
• sd0
• sda
• sdf
• sldm
• sldx
• sql
• sqlite
• sqlite3
• sqlitedb
• sr2
• srf
• srt
• srw
• st4
• st5
• st6
• st7
• st8
• std
• sti
• stw
• stx
• svg
• swf
• sxc
• sxd
• sxg
• sxi
• sxi
• sxm
• sxw
• tex
• tga
• thm
• tlg
• txt
• vob
• wallet
• wav
• wb2
• wmv
• wpd
• wps
• x11
• x3f
• xis
• xla
• xlam
• xlk
• xlm
• xlr
• xls
• xlsb
• xlsm
• xlsx
• xlt
• xltm
• xltx
• xlw
• ycbcra
• yuv
• zip
• +MuhD

It deletes the initially executed copy of itself

NOTES:

It searches all drives for files to encrypt except CD_ROM drive.

It avoids encrypting files inside the following directories:

• windows
• temp
• .
• ..
• cache
• Y@Cs
• uvOyR
• nvidia
• games
• packages

It terminates and uninstalls itself if geo-location of the affected machine matches any of the following country codes:

• BY (BELARUS)
• UA (UKRAINE)
• RU (RUSSIA)
• KZ (KAZAKHSTAN)
• AM (ARMENIA)
• RS (SERBIA)
• IR (IRAN)

It deletes shadow copies by executing the following command:

• vssadmin.exe Delete Shadows /All /Quiet

It drops HELP_DECRYPT.HTML, HELP_DECRYPT.PNG, HELP_DECRYPT.TXT, and HELP_DECRYPT.URL to all folders where files are encrypted. It opens the dropped ransom notes HELP_DECRYPT.TXT, HELP_DECRYPT.PNG and HELP_DECRYPT.HTML:

It demands payment for using decryption service: