Ransom_CERBER.VSAHBR

 Analysis by: Byron Jon Gelera

 ALIASES:

Ransom.Cerber (Symantec); Trojan-Ransom.Win32.Zerber.ejma (Kaspersky)

 PLATFORM:

Windows

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:
 INFORMATION EXPOSURE:

  • Threat Type: Ransomware

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Downloaded from the Internet

This Ransomware may be downloaded by other malware/grayware from remote sites.

It connects to certain websites to send and receive information.

It encrypts files with specific file extensions. It drops files as ransom note.

  TECHNICAL DETAILS

File Size:

320,760 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

21 Jul 2017

Payload:

Displays images, Encrypts files

Arrival Details

This Ransomware may be downloaded by the following malware/grayware from remote sites:

Installation

This Ransomware drops the following files:

  • %User Temp%\{random characters}\{random characters}.tmp
  • %User Temp%\tmp{random}.bmp ← Ransom note wallpaper

(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.)

Other System Modifications

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

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

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

Other Details

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

  • http://{BLOCKED}rilkjced3j.1n5mod.top
  • {BLOCKED}.{BLOCKED}.12.0/27:6893
  • {BLOCKED}.{BLOCKED}.200.0/27:6893
  • {BLOCKED}.{BLOCKED}.176.0/22:6893

It does the following:

  • It avoids infecting system with the following OS Language Code:
    • 1049 - Russian
    • 1058 - Ukrainian
    • 1059 - Belarusian
    • 1064 - Tajik (Cyrillic)
    • 1067 - Armenian
    • 1068 - Azeri (Latin)
    • 1079 - Georgian
    • 1087 - Kazakh
    • 1088 - Kyrgyz
    • 1090 - Turkmen
    • 1091 - Uzbek (Latin)
    • 1092 - Tatar
    • 2072 - Romanian (Moldova)
    • 2073 - Romanian (Romania)
    • 2092 - Azeri (Cyrillic)
    • 2115 - Uzbek (Cyrillic)
  • It is configured to target related files under 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 file extensions:
    • .bat
    • .cmd
    • .com
    • .cpl
    • .dll
    • .exe
    • .hta
    • .msc
    • .msi
    • .msp
    • .pif
    • .scf
    • .scr
    • .sys

Ransomware Routine

This Ransomware encrypts files with the following extensions:

  • .123
  • .1cd
  • .3dm
  • .3ds
  • .3fr
  • .3g2
  • .3gp
  • .3pr
  • .602
  • .7z
  • .7zip
  • .aac
  • .ab4
  • .abd
  • .acc
  • .accdb
  • .accde
  • .accdr
  • .accdt
  • .ach
  • .acr
  • .act
  • .adb
  • .adp
  • .ads
  • .aes
  • .agdl
  • .ai
  • .aiff
  • .ait
  • .al
  • .aoi
  • .apj
  • .apk
  • .arc
  • .arw
  • .ascx
  • .asf
  • .asm
  • .asp
  • .aspx
  • .asset
  • .asx
  • .atb
  • .avi
  • .awg
  • .back
  • .backup
  • .backupdb
  • .bak
  • .bank
  • .bat
  • .bay
  • .bdb
  • .bgt
  • .bik
  • .bin
  • .bkp
  • .blend
  • .bmp
  • .bpw
  • .brd
  • .bsa
  • .bz2
  • .c
  • .cash
  • .cdb
  • .cdf
  • .cdr
  • .cdr3
  • .cdr4
  • .cdr5
  • .cdr6
  • .cdrw
  • .cdx
  • .ce1
  • .ce2
  • .cer
  • .cfg
  • .cfn
  • .cgm
  • .cib
  • .class
  • .cls
  • .cmd
  • .cmt
  • .config
  • .contact
  • .cpi
  • .cpp
  • .cr2
  • .craw
  • .crt
  • .crw
  • .cry
  • .cs
  • .csh
  • .csl
  • .csr
  • .css
  • .csv
  • .d3dbsp
  • .dac
  • .das
  • .dat
  • .db
  • .db3
  • .db_journal
  • .dbf
  • .dbx
  • .dc2
  • .dch
  • .dcr
  • .dcs
  • .ddd
  • .ddoc
  • .ddrw
  • .dds
  • .def
  • .der
  • .des
  • .design
  • .dgc
  • .dgn
  • .dif
  • .dip
  • .dit
  • .djv
  • .djvu
  • .dng
  • .doc
  • .docb
  • .docm
  • .docx
  • .dot
  • .dotm
  • .dotx
  • .drf
  • .drw
  • .dtd
  • .dwg
  • .dxb
  • .dxf
  • .dxg
  • .edb
  • .eml
  • .eps
  • .erbsql
  • .erf
  • .exf
  • .fdb
  • .ffd
  • .fff
  • .fh
  • .fhd
  • .fla
  • .flac
  • .flb
  • .flf
  • .flv
  • .forge
  • .fpx
  • .frm
  • .fxg
  • .gbr
  • .gho
  • .gif
  • .gpg
  • .gray
  • .grey
  • .groups
  • .gry
  • .gz
  • .h
  • .hbk
  • .hdd
  • .hpp
  • .html
  • .hwp
  • .ibank
  • .ibd
  • .ibz
  • .idx
  • .iif
  • .iiq
  • .incpas
  • .indd
  • .info
  • .info_
  • .iwi
  • .jar
  • .java
  • .jnt
  • .jpe
  • .jpeg
  • .jpg
  • .js
  • .json
  • .k2p
  • .kc2
  • .kdbx
  • .kdc
  • .key
  • .kpdx
  • .kwm
  • .laccdb
  • .lay
  • .lay6
  • .lbf
  • .lck
  • .ldf
  • .lit
  • .litemod
  • .litesql
  • .lock
  • .ltx
  • .lua
  • .m
  • .m2ts
  • .m3u
  • .m4a
  • .m4p
  • .m4u
  • .m4v
  • .ma
  • .mab
  • .mapimail
  • .max
  • .mbx
  • .md
  • .mdb
  • .mdc
  • .mdf
  • .mef
  • .mfw
  • .mid
  • .mkv
  • .mlb
  • .mml
  • .mmw
  • .mny
  • .money
  • .moneywell
  • .mos
  • .mov
  • .mp3
  • .mp4
  • .mpeg
  • .mpg
  • .mrw
  • .ms11
  • .msf
  • .msg
  • .mts
  • .myd
  • .myi
  • .nd
  • .ndd
  • .ndf
  • .nef
  • .nk2
  • .nop
  • .nrw
  • .ns2
  • .ns3
  • .ns4
  • .nsd
  • .nsf
  • .nsg
  • .nsh
  • .nvram
  • .nwb
  • .nx2
  • .nxl
  • .nyf
  • .oab
  • .obj
  • .odb
  • .odc
  • .odf
  • .odg
  • .odm
  • .odp
  • .ods
  • .odt
  • .ogg
  • .oil
  • .omg
  • .one
  • .onenotec2
  • .orf
  • .ost
  • .otg
  • .oth
  • .otp
  • .ots
  • .ott
  • .p12
  • .p7b
  • .p7c
  • .pab
  • .pages
  • .paq
  • .pas
  • .pat
  • .pbf
  • .pcd
  • .pct
  • .pdb
  • .pdd
  • .pdf
  • .pef
  • .pem
  • .pfx
  • .php
  • .pif
  • .pl
  • .plc
  • .plus_muhd
  • .pm
  • .pm!
  • .pmi
  • .pmj
  • .pml
  • .pmm
  • .pmo
  • .pmr
  • .pnc
  • .pnd
  • .png
  • .pnx
  • .pot
  • .potm
  • .potx
  • .ppam
  • .pps
  • .ppsm
  • .ppsx
  • .ppt
  • .pptm
  • .pptx
  • .prf
  • .private
  • .ps
  • .psafe3
  • .psd
  • .pspimage
  • .pst
  • .ptx
  • .pub
  • .pwm
  • .py
  • .qba
  • .qbb
  • .qbm
  • .qbr
  • .qbw
  • .qbx
  • .qby
  • .qcow
  • .qcow2
  • .qed
  • .qtb
  • .r3d
  • .raf
  • .rar
  • .rat
  • .raw
  • .rb
  • .rdb
  • .re4
  • .rm
  • .rtf
  • .rvt
  • .rw2
  • .rwl
  • .rwz
  • .s3db
  • .safe
  • .sas7bdat
  • .sav
  • .save
  • .say
  • .sch
  • .sd0
  • .sda
  • .sdb
  • .sdf
  • .secret
  • .sh
  • .sldm
  • .sldx
  • .slk
  • .slm
  • .sql
  • .sqlite
  • .sqlite-shm
  • .sqlite-wal
  • .sqlite3
  • .sqlitedb
  • .sr2
  • .srb
  • .srf
  • .srs
  • .srt
  • .srw
  • .st4
  • .st5
  • .st6
  • .st7
  • .st8
  • .stc
  • .std
  • .sti
  • .stl
  • .stm
  • .stw
  • .stx
  • .svg
  • .swf
  • .sxc
  • .sxd
  • .sxg
  • .sxi
  • .sxm
  • .sxw
  • .tar
  • .tax
  • .tbb
  • .tbk
  • .tbn
  • .tex
  • .tga
  • .tgz
  • .thm
  • .tif
  • .tiff
  • .tlg
  • .tlx
  • .txt
  • .uop
  • .uot
  • .upk
  • .usr
  • .vb
  • .vbox
  • .vbs
  • .vdi
  • .vhd
  • .vhdx
  • .vmdk
  • .vmsd
  • .vmx
  • .vmxf
  • .vob
  • .vpd
  • .vsd
  • .wab
  • .wad
  • .wallet
  • .war
  • .wav
  • .wb2
  • .wk1
  • .wks
  • .wma
  • .wmf
  • .wmv
  • .wpd
  • .wps
  • .x11
  • .x3f
  • .xis
  • .xla
  • .xlam
  • .xlc
  • .xlk
  • .xlm
  • .xlr
  • .xls
  • .xlsb
  • .xlsm
  • .xlsx
  • .xlt
  • .xltm
  • .xltx
  • .xlw
  • .xml
  • .xps
  • .xxx
  • .ycbcra
  • .yuv
  • .zip

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\
  • :\msocache\
  • :\perflogs\
  • :\program files (x86)\
  • :\program files\
  • :\programdata\
  • :\recovery\
  • :\recycled\
  • :\recycler\
  • :\system volume information\
  • :\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 renames encrypted files using the following names:

  • {10 Random Characters}.{4 Random Characters}

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

  • {folder of encrypted files}\_R_E_A_D___T_H_I_S___{random}_.txt
  • {folder of encrypted files}\_R_E_A_D___T_H_I_S___{random}_.hta
  • %Desktop%\_R_E_A_D___T_H_I_S___{random}_.txt
  • %Desktop%\_R_E_A_D___T_H_I_S___{random}_.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.)

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

NOTES:

The _R_E_A_D___T_H_I_S___{random}_.hta contains the following information:

  SOLUTION

Minimum Scan Engine:

9.850

FIRST VSAPI PATTERN FILE:

13.546.08

FIRST VSAPI PATTERN DATE:

21 Jul 2017

VSAPI OPR PATTERN File:

13.547.00

VSAPI OPR PATTERN Date:

22 Jul 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

Search and delete these files

[ Learn More ]
There may be some files that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the "More advanced options" option to include all hidden files and folders in the search result.  
  • %User Temp%\{random characters}\{random characters}.tmp
  • %User Temp%\tmp{random}.bmp
  • {folder of encrypted files}\_R_E_A_D___T_H_I_S___{random}_.txt
  • {folder of encrypted files}\_R_E_A_D___T_H_I_S___{random}_.hta
  • %Desktop%\_R_E_A_D___T_H_I_S___{random}_.txt
  • %Desktop%\_R_E_A_D___T_H_I_S___{random}_.hta

Step 4

Scan your computer with your Trend Micro product to delete files detected as Ransom_CERBER.VSAHBR. 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 5

Restore encrypted files from backup.

Step 6

Reset your Desktop properties

[ Learn More ]


Did this description help? Tell us how we did.