RANSOM_CRYPSHED.BZV
Win32/Filecoder.ED (ESET-NOD32); Ransom.Troldesh (Malwarebytes)
Windows
Threat Type: Ransomware
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
Downloaded from the Internet, Dropped by other malware
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.
TECHNICAL DETAILS
1,440,335 bytes
Yes
12 Apr 2017
Encrypts files, Connects to URLs/IPs
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:
- %All Users Profile%\Application Data\Windows\csrss.exe (Windows XP and below)
- %All Users Profile%\Windows\csrss.exe (Windows Vista and above)
(Note: %All Users Profile% is the All Users folder, where it usually is C:\Documents and Settings\All Users on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\ProgramData 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.)
Autostart Technique
This Ransomware adds the following registry entries to enable its automatic execution at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Client Server Runtime Subsystem = %All Users Profile%\Windows\csrss.exe (Windows Vista and above)
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Client Server Runtime Subsystem = %All Users Profile%\Application Data\Windows\csrss.exe (Windows XP and below)
Other System Modifications
This Ransomware adds the following registry keys:
HKEY_LOCAL_MACHINE\SOFTWARE\System32\
Configuration
It adds the following registry entries:
HKEY_LOCAL_MACHINE\SOFTWARE\System32\
Configuration
xVersion = 4.0.0.1
HKEY_LOCAL_MACHINE\SOFTWARE\System32\
Configuration
xpk = {PUBLIC KEY}
HKEY_LOCAL_MACHINE\SOFTWARE\System32\
Configuration
xmode = {mode}
HKEY_LOCAL_MACHINE\SOFTWARE\System32\
Configuration
xi = {ID}
HKEY_LOCAL_MACHINE\SOFTWARE\System32\
Configuration
xstate = {state}
HKEY_LOCAL_MACHINE\SOFTWARE\System32\
Configuration
xcnt = {encrypted files count}
HKEY_LOCAL_MACHINE\SOFTWARE\System32\
Configuration
shsnt = {number}
HKEY_LOCAL_MACHINE\SOFTWARE\System32\
Configuration
shst = {number}
HKEY_LOCAL_MACHINE\SOFTWARE\System32\
Configuration
sh1 = {random}
HKEY_LOCAL_MACHINE\SOFTWARE\System32\
Configuration
sh2 = {random}
It sets the system's desktop wallpaper to the following image:
Dropping Routine
This Ransomware drops the following files:
- %User Temp%\6893A5D897\lock
- %User Temp%\6893A5D897\state
- %User Temp%\6893A5D897\unverified-microdesc-consensus
- %User Temp%\6893A5D897\cached-certs
- %User Temp%\6893A5D897\cached-microdesc-consensus
- %User Temp%\6893A5D897\cached-microdescs.new
- {drive letter}:\README{1-10}.txt → Ransom Note
- {folder containing encrypted files}\README.txt → Ransom Note
- %ProgramData%\System32\xfs (Hidden) → Contains list of encrypted files
(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp 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.. %ProgramData% is the Program Data folder, where it usually is C:\Program Files in Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\ProgramData 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 URL(s) to get the affected system's IP address:
- http://whatismyipaddress.com/
- http://whatsmyip.net/
It connects to the following website to send and receive information:
- http://{server}/{path}
where {server} can be any of the following:- {BLOCKED}.{BLOCKED}.40.189
- {BLOCKED}.{BLOCKED}.0.39
- {BLOCKED}.{BLOCKED}.176.148
- {BLOCKED}.{BLOCKED}.81.226
- {BLOCKED}.{BLOCKED}.232.207
- {BLOCKED}.{BLOCKED}.225.155
- {BLOCKED}.{BLOCKED}.249.221
- {BLOCKED}.{BLOCKED}.6.199
- {BLOCKED}.{BLOCKED}.221.166
- {BLOCKED}.{BLOCKED}.220.54
- {BLOCKED}xclh6fd.onion
where {path} can be any of the following:- reg.php
- prog.php
- err.php
- cmd.php
- sys.php
- shd.php
It encrypts files with the following extensions:
- .1cd
- .3ds
- .3fr
- .3g2
- .3gp
- .7z
- .accda
- .accdb
- .accdc
- .accde
- .accdt
- .accdw
- .adb
- .adp
- .ai
- .ai3
- .ai4
- .ai5
- .ai6
- .ai7
- .ai8
- .anim
- .arw
- .as
- .asa
- .asc
- .ascx
- .asm
- .asmx
- .asp
- .aspx
- .asr
- .asx
- .avi
- .avs
- .backup
- .bak
- .bay
- .bd
- .bin
- .bmp
- .bz2
- .c
- .cbf
- .cdr
- .cer
- .cf
- .cfc
- .cfm
- .cfml
- .cfu
- .chm
- .cin
- .class
- .clx
- .config
- .cpp
- .cr2
- .crt
- .crw
- .crypted
- .cs
- .css
- .csv
- .cub
- .dae
- .dat
- .db
- .dbf
- .dbx
- .dc3
- .dcm
- .dcr
- .der
- .dib
- .dic
- .dif
- .divx
- .djvu
- .dmp
- .dng
- .doc
- .docm
- .docx
- .dot
- .dotm
- .dotx
- .dpx
- .dqy
- .dsn
- .dt
- .dtd
- .dwg
- .dwt
- .dx
- .dxf
- .edml
- .efd
- .elf
- .emf
- .eml
- .emz
- .epf
- .eps
- .epsf
- .epsp
- .erf
- .exr
- .f4v
- .fbk
- .fdb
- .fido
- .fld
- .flm
- .flv
- .frm
- .fxg
- .geo
- .gif
- .grs
- .gz
- .h
- .hdr
- .hpp
- .hta
- .htc
- .htm
- .html
- .icb
- .ics
- .iff
- .inc
- .indd
- .ini
- .iqy
- .j2c
- .j2k
- .java
- .jp2
- .jpc
- .jpe
- .jpeg
- .jpf
- .jpg
- .jpx
- .js
- .jsf
- .json
- .jsp
- .kdc
- .kmz
- .kwm
- .lasso
- .lbi
- .lgf
- .lgp
- .log
- .lst
- .m1v
- .m4a
- .m4v
- .max
- .md
- .mda
- .mdb
- .mde
- .mdf
- .mdw
- .mef
- .mft
- .mfw
- .mht
- .mhtml
- .mka
- .mkidx
- .mkv
- .mos
- .mov
- .mp3
- .mp4
- .mpeg
- .mpg
- .mpv
- .mrw
- .msg
- .mtr
- .mxl
- .myd
- .myi
- .nef
- .nrw
- .obj
- .odb
- .odc
- .odm
- .odp
- .ods
- .oft
- .one
- .onepkg
- .onetoc2
- .opt
- .oqy
- .orf
- .p12
- .p7b
- .p7c
- .pam
- .pbm
- .pct
- .pcx
- .pdd
- .pdd
- .pdp
- .pef
- .pem
- .pff
- .pfm
- .pfx
- .pgm
- .php
- .php3
- .php4
- .php5
- .phtml
- .pict
- .pl
- .pls
- .pm
- .png
- .pnm
- .pot
- .potm
- .potx
- .ppa
- .ppam
- .ppm
- .pps
- .ppsm
- .ppt
- .pptm
- .pptx
- .prn
- .ps
- .psb
- .psd
- .pst
- .pst
- .ptx
- .pub
- .pwm
- .pxr
- .py
- .qt
- .r3d
- .raf
- .rar
- .raw
- .rdf
- .rgbe
- .rle
- .rqy
- .rss
- .rtf
- .rw2
- .rwl
- .safe
- .sct
- .sdpx
- .shtm
- .shtml
- .slk
- .sln
- .sql
- .sr2
- .srf
- .srw
- .ssi
- .st
- .stm
- .svg
- .svgz
- .swf
- .tab
- .tar
- .tbb
- .tbi
- .tbk
- .tdi
- .tga
- .thmx
- .tib
- .tif
- .tiff
- .tld
- .torrent
- .tpl
- .txt
- .u3d
- .udl
- .uxdc
- .vault
- .vb
- .vbk
- .vbm
- .vbs
- .vcs
- .vda
- .vdr
- .vdw
- .vdx
- .vhd
- .vib
- .vrp
- .vsd
- .vss
- .vst
- .vsw
- .vsx
- .vtm
- .vtml
- .vtx
- .wav
- .wb2
- .wbm
- .wbmp
- .wim
- .wmf
- .wml
- .wmv
- .wpd
- .wps
- .x3f
- .xl
- .xla
- .xlam
- .xlk
- .xlm
- .xls
- .xlsb
- .xlsm
- .xlsx
- .xlt
- .xltm
- .xltx
- .xlw
- .xml
- .xps
- .xsd
- .xsf
- .xsl
- .xslt
- .xsn
- .xtp
- .xtp2
- .xyze
- .xz
- .zip
It renames encrypted files using the following names:
- {random characters}=.{ID}.no_more_ransom
It does the following:
- It delets shadow copies by executing the following commands:
- %System%\vssadmin.exe Delete Shadows /All /Quiet
(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)
NOTES:
The ransom note contains the following message:
SOLUTION
9.850
13.336.04
12 Apr 2017
13.337.00
13 Apr 2017
Step 1
Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.
Step 2
Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.
Step 3
Restart in Safe Mode
Step 4
Delete this registry key
Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.
- In HKEY_LOCAL_MACHINE\SOFTWARE\System32
- Configuration
- Configuration
Step 5
Delete this registry value
Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- Client Server Runtime Subsystem = %All Users Profile%\Application Data\Windows\csrss.exe (Windows XP and below)
- Client Server Runtime Subsystem = %All Users Profile%\Application Data\Windows\csrss.exe (Windows XP and below)
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- Client Server Runtime Subsystem = %All Users Profile%\Windows\csrss.exe (Windows Vista and above)
- Client Server Runtime Subsystem = %All Users Profile%\Windows\csrss.exe (Windows Vista and above)
Step 6
Search and delete this file
- %User Temp%\6893A5D897\lock
- %User Temp%\6893A5D897\state
- %User Temp%\6893A5D897\unverified-microdesc-consensus
- %User Temp%\6893A5D897\cached-certs
- %User Temp%\6893A5D897\cached-microdesc-consensus
- {drive letter}:\README{1-10}.txt
- {folder containing encrypted files}\README.txt
- %ProgramData%\System32\xfs
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as RANSOM_CRYPSHED.BZV. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.
Step 8
Restore encrypted files from backup.
Step 9
Reset your Desktop properties
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