Analysis by: Joshua John Bantayan
ALIASES:

Trojan.Win32.DelShad.fxd (KASPERSKY); Trojan.Win32.Gencbl (IKARUS)

 PLATFORM:

Windows

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

  • Threat Type: Ransomware

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel: Downloaded from the Internet

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 encrypts files found in specific folders. It drops files as ransom note. It avoids encrypting files with the following file extensions.

  TECHNICAL DETAILS

File Size: 3,316,376 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 23 Mar 2021
Payload: Displays message/message boxes, Encrypts files, Terminates processes

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 files:

  • %Application Data%\KEY.FILE

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

It adds the following processes:

  • vssadmin.exe Resize ShadowStorage /for=c: /on=c: /maxsize=401MB
  • vssadmin.exe Resize ShadowStorage /for=c: /on=c: /maxsize=unbounded
  • vssadmin.exe Resize ShadowStorage /for=d: /on=d: /maxsize=401MB
  • vssadmin.exe Resize ShadowStorage /for=d: /on=d: /maxsize=unbounded
  • vssadmin.exe Resize ShadowStorage /for=e: /on=e: /maxsize=401MB
  • vssadmin.exe Resize ShadowStorage /for=e: /on=e: /maxsize=unbounded
  • vssadmin.exe Resize ShadowStorage /for=f: /on=f: /maxsize=401MB
  • vssadmin.exe Resize ShadowStorage /for=f: /on=f: /maxsize=unbounded
  • vssadmin.exe Resize ShadowStorage /for=g: /on=g: /maxsize=401MB
  • vssadmin.exe Resize ShadowStorage /for=g: /on=g: /maxsize=unbounded
  • vssadmin.exe Resize ShadowStorage /for=h: /on=h: /maxsize=401MB
  • vssadmin.exe Resize ShadowStorage /for=h: /on=h: /maxsize=unbounded
  • vssadmin.exe Delete Shadows /All /Quiet
  • del /s /f /q c:\*.VHD c:\*.bac c:\*.bak c:\*.wbcat c:\*.bkf c:\Backup*.* c:\backup*.* c:\*.set c:\*.win c:\*.dsk
  • del /s /f /q d:\*.VHD d:\*.bac d:\*.bak d:\*.wbcat d:\*.bkf d:\Backup*.* d:\backup*.* d:\*.set d:\*.win d:\*.dsk
  • del /s /f /q e:\*.VHD e:\*.bac e:\*.bak e:\*.wbcat e:\*.bkf e:\Backup*.* e:\backup*.* e:\*.set e:\*.win e:\*.dsk
  • del /s /f /q f:\*.VHD f:\*.bac f:\*.bak f:\*.wbcat f:\*.bkf f:\Backup*.* f:\backup*.* f:\*.set f:\*.win f:\*.dsk
  • del /s /f /q g:\*.VHD g:\*.bac g:\*.bak g:\*.wbcat g:\*.bkf g:\Backup*.* g:\backup*.* g:\*.set g:\*.win g:\*.dsk
  • del /s /f /q h:\*.VHD h:\*.bac h:\*.bak h:\*.wbcat h:\*.bkf h:\Backup*.* h:\backup*.* h:\*.set h:\*.win h:\*.dsk
  • del %0
  • bcdedit.exe /set {default} recoveryenabled No
  • bcdedit.exe /set {default} bootstatuspolicy ignoreallfailures
  • wbadmin DELETE SYSTEMSTATEBACKUP
  • wbadmin DELETE SYSTEMSTATEBACKUP -deleteOldest
  • wmic.exe SHADOWCOPY /nointeractive
  • %System%\cmd.exe /c del {Malware File Path}\{Malware File Name}.exe >>NUL → delete itself after execution

(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

It adds the following mutexes to ensure that only one of its copies runs at any one time:

  • {8761ABBD-7F85-42EE-B272-A76179687C63}

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
MSFEEditor = "{Malware File Path}\{Malware File Name.exe}" e

It starts the following services:

  • Lanmanworkstation

Other System Modifications

This Ransomware adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Policies\
System
EnabledLinkedConnections = 1

Process Termination

This Ransomware terminates the following services if found on the affected system:

  • ccEvtMgr
  • ccSetMgr
  • Culserver
  • dbeng8
  • dbsrv12
  • DefWatch
  • Intuit.QuickBooks.FCS
  • MsDtsServer100
  • msmdsrv
  • MSSQLFDLauncher
  • MSSQLSERVER
  • MSSQLServerADHelper100
  • MSSQLServerOLAPService
  • QBCFMonitorService
  • QBIDPService
  • ReportServer
  • RTVscan
  • SavRoam
  • sqladhlp
  • SQLADHLP
  • sqlagent
  • sqlbrowser
  • SQLBrowser
  • SQLSERVERAGENT
  • sqlservr
  • sqlwriter
  • SQLWriter
  • tomcat6
  • vmware-converter
  • vmware-usbarbitator64
  • wrapper
  • zhudongfangyu
  • ccEvtMgr
  • ccSetMgr
  • Culserver
  • dbeng8
  • dbsrv12
  • DefWatch
  • Intuit.QuickBooks.FCS
  • MsDtsServer100
  • msmdsrv
  • MSSQLFDLauncher
  • MSSQLSERVER
  • MSSQLServerADHelper100
  • MSSQLServerOLAPService
  • QBCFMonitorService
  • QBIDPService
  • ReportServer
  • RTVscan
  • SavRoam
  • sqladhlp
  • SQLADHLP
  • sqlagent
  • sqlbrowser
  • SQLBrowser
  • SQLSERVERAGENT
  • sqlservr
  • sqlwriter
  • SQLWriter
  • tomcat6
  • vmware-converter
  • vmware-usbarbitator64
  • wrapper
  • zhudongfangyu

It terminates the following processes if found running in the affected system's memory:

  • 360doctor.exe
  • 360se.exe
  • axlbridge.exe
  • Culture.exe
  • Defwatch.exe
  • EXCEL.EXE
  • fdhost.exe
  • fdlauncher.exe
  • GDscan.exe
  • httpd.exe
  • java.exe
  • MsDtsSrvr.exe
  • onenotem.exe
  • QBCFMonitorService.exe
  • QBDBMgr.exe
  • QBIDPService.exe
  • qbupdate.exe
  • QBW32.exe
  • RAgui.exe
  • RTVscan.exe
  • sqlbrowser.exe
  • sqlmangr.exe
  • sqlservr.exe
  • sqlwriter.exe
  • ssms.exe
  • supervise.exe
  • tomcat6.exe
  • wdswfsafe.exe
  • winword.exe
  • Winword.exe
  • wxServer.exe
  • wxServerView
  • ZhuDongFangYu.exe

Other Details

This Ransomware encrypts files with the following extensions:

  • .123
  • .1c
  • .1cd
  • .3dm
  • .3ds
  • .3fr
  • .3g2
  • .3gp
  • .3pr
  • .602
  • .7z
  • .7zip
  • ._ms
  • .aac
  • .ab4
  • .abd
  • .accdb
  • .accde
  • .accdr
  • .accdt
  • .ace
  • .ach
  • .acr
  • .act
  • .adb
  • .adi
  • .adp
  • .adr
  • .ads
  • .aes
  • .afi
  • .agdl
  • .ai
  • .aiff
  • .aii
  • .air
  • .ais
  • .ait
  • .aiv
  • .al
  • .alg
  • .allet
  • .ams
  • .aocla
  • .aoi
  • .apj
  • .apk
  • .arc
  • .arch00
  • .arm
  • .art
  • .arw
  • .arz
  • .asc
  • .asf
  • .asm
  • .asp
  • .aspx
  • .asset
  • .asx
  • .avhdx
  • .avi
  • .awg
  • .backup
  • .backupdb
  • .bank
  • .bar
  • .bat
  • .bay
  • .bc6
  • .bc7
  • .bck
  • .bco
  • .bdb
  • .bgt
  • .big
  • .bik
  • .bin
  • .bkf
  • .bkp
  • .bkup
  • .blend
  • .blob
  • .bmp
  • .bpn
  • .bpw
  • .brd
  • .bsa
  • .bsm
  • .bxl
  • .bz2
  • .c
  • .cad
  • .cam
  • .cas
  • .cbk
  • .cbu
  • .cdf
  • .cdr
  • .cdr3
  • .cdr4
  • .cdr5
  • .cdr6
  • .cdrw
  • .cdx
  • .ce1
  • .ce2
  • .cel
  • .cer
  • .cert
  • .cf
  • .cfg
  • .cfr
  • .cgi
  • .cgm
  • .chg
  • .cib
  • .ckt
  • .class
  • .classpath
  • .cls
  • .cmd
  • .cmt
  • .cnf
  • .con
  • .config
  • .contact
  • .cpa
  • .cpi
  • .cpp
  • .cpr
  • .cr2
  • .craw
  • .crt
  • .crw
  • .cs
  • .csa
  • .csh
  • .cshtml
  • .csl
  • .csr
  • .css
  • .csv
  • .ctl
  • .cwz
  • .d
  • .d3dbsp
  • .dac
  • .das
  • .data
  • .dazip
  • .db0
  • .db3
  • .db5
  • .db_journal
  • .dba
  • .dbc
  • .dbf
  • .dbs
  • .dbx
  • .dc2
  • .dch
  • .dcr
  • .dcs
  • .ddb
  • .ddd
  • .ddoc
  • .ddrw
  • .dds
  • .der
  • .des
  • .desc
  • .design
  • .dft
  • .dgc
  • .dif
  • .dip
  • .dit
  • .djvu
  • .dmp
  • .dng
  • .doc
  • .docb
  • .docm
  • .docx
  • .dot
  • .dotm
  • .dotx
  • .dra
  • .drf
  • .drl
  • .dru
  • .drw
  • .dsn
  • .dsnwrk
  • .dt
  • .dtd
  • .dwg
  • .dxb
  • .dxf
  • .dxg
  • .e
  • .ecf
  • .edb
  • .edf
  • .elt
  • .eml
  • .emz
  • .epk
  • .eps
  • .erbsql
  • .erf
  • .esm
  • .ewprj
  • .exf
  • .fdb
  • .ff
  • .ffd
  • .fff
  • .fh
  • .fhd
  • .fla
  • .flac
  • .flf
  • .flp
  • .flv
  • .flvv
  • .fods
  • .fodt
  • .forge
  • .fos
  • .fp7
  • .fpd
  • .fpk
  • .fpx
  • .frm
  • .fsh
  • .fxg
  • .g1
  • .g2
  • .g3
  • .g4
  • .gbk
  • .gbl
  • .gbo
  • .gbp
  • .gbr
  • .gbs
  • .gbx
  • .gdb
  • .gho
  • .gif
  • .gko
  • .gml
  • .gp
  • .gp1
  • .gp2
  • .gp3
  • .gp4
  • .gpb
  • .gpg
  • .gpt
  • .gray
  • .grb
  • .grey
  • .groups
  • .gry
  • .gtl
  • .gto
  • .gtp
  • .gts
  • .gwk
  • .gz
  • .h
  • .hbk
  • .hdd
  • .hkdb
  • .hkx
  • .hplg
  • .hpp
  • .html
  • .hvpl
  • .hwp
  • .ibank
  • .ibd
  • .ibz
  • .icxs
  • .idb
  • .idc
  • .idx
  • .iif
  • .iiq
  • .incpas
  • .indd
  • .info
  • .ip
  • .ink
  • .ipc
  • .ism
  • .iso
  • .itdb
  • .itl
  • .itm
  • .iwd
  • .iwi
  • .ix
  • .jar
  • .java
  • .jnt
  • .jpe
  • .jpeg
  • .jpg
  • .jrl
  • .js
  • .jsp
  • .kc2
  • .kdb
  • .kdbx
  • .kdc
  • .kf
  • .kicad
  • .kpdx
  • .kwm
  • .laccdb
  • .lay
  • .lay6
  • .layout
  • .lbf
  • .lbr
  • .lc
  • .lck
  • .ldb
  • .ldf
  • .lg
  • .lgc
  • .lia
  • .lib
  • .libprj
  • .license
  • .licz
  • .lit
  • .litemod
  • .llx
  • .lmc
  • .log
  • .lrf
  • .ltx
  • .lua
  • .lvl
  • .lyt
  • .lzh
  • .lzma
  • .m
  • .m2
  • .m2ts
  • .m3u
  • .m4a
  • .m4p
  • .m4u
  • .m4v
  • .map
  • .mapimail
  • .max
  • .mbx
  • .mcmeta
  • .md
  • .mdb
  • .mdbackup
  • .mdc
  • .mddata
  • .mdf
  • .mef
  • .menu
  • .mfw
  • .mid
  • .mkv
  • .mlb
  • .mlx
  • .mml
  • .mmw
  • .mny
  • .moneywell
  • .mos
  • .mov
  • .mp3
  • .mp4
  • .mpeg
  • .mpg
  • .mpqge
  • .mrg
  • .mrw
  • .mrwref
  • .msg
  • .mst
  • .mts
  • .myd
  • .myi
  • .mysql
  • .mysqli
  • .nbd
  • .nc
  • .ncf
  • .nd
  • .ndd
  • .ndf
  • .nef
  • .nk2
  • .nop
  • .nrw
  • .ns2
  • .ns3
  • .ns4
  • .nsd
  • .nsf
  • .nsg
  • .nsh
  • .ntl
  • .nvram
  • .nwb
  • .nx2
  • .nxl
  • .nyf
  • .oab
  • .obj
  • .obk
  • .odb
  • .odc
  • .odf
  • .odg
  • .odm
  • .odp
  • .ods
  • .odt
  • .oeb
  • .ogg
  • .oil
  • .olb
  • .one
  • .onetoc2
  • .opj
  • .opt
  • .ora
  • .orf
  • .ost
  • .otg
  • .oth
  • .otp
  • .ots
  • .ott
  • .p
  • .p12
  • .p7b
  • .p7c
  • .pab
  • .pad
  • .pages
  • .pak
  • .paq
  • .par
  • .pas
  • .pat
  • .pbd
  • .pc
  • .pcb
  • .pcbdoc
  • .pcd
  • .pct
  • .pdb
  • .pdblib
  • .pdd
  • .pdf
  • .pef
  • .pem
  • .pfx
  • .phj
  • .phl
  • .pho
  • .php
  • .pif
  • .pkpass
  • .pl
  • .plc
  • .plus_muhd
  • .png
  • .pot
  • .potm
  • .potx
  • .ppam
  • .ppc
  • .pps
  • .ppsm
  • .ppsx
  • .ppt
  • .pptm
  • .pptx
  • .prf
  • .prj
  • .prjcor
  • .prjemb
  • .prjpcb
  • .pro
  • .project
  • .prt
  • .ps
  • .ps1
  • .psafe3
  • .psc
  • .psd
  • .psk
  • .psm
  • .pspimage
  • .pst
  • .pt
  • .ptx
  • .pwm
  • .py
  • .q99
  • .qb1
  • .qba
  • .qbb
  • .qbk
  • .qbm
  • .qbmb
  • .qbmd
  • .qbquery
  • .qbr
  • .qbw
  • .qbx
  • .qby
  • .qcow
  • .qcow2
  • .qdf
  • .qed
  • .qfd
  • .qfx
  • .qic
  • .qif
  • .qmd
  • .qry
  • .quicken
  • .quicken2015backup
  • .quicken2016backup
  • .quicken2017backup
  • .qw5
  • .r3d
  • .raf
  • .rar
  • .rat
  • .raw
  • .rb
  • .rdb
  • .re4
  • .reu
  • .rgss3a
  • .rim
  • .rm
  • .rofl
  • .rou
  • .rtf
  • .rul
  • .rvt
  • .rw2
  • .rwl
  • .rwz
  • .s3db
  • .safe
  • .sal
  • .sas7bdat
  • .sav
  • .save
  • .say
  • .sb
  • .sbn
  • .sbx
  • .sch
  • .schdoc
  • .schlib
  • .sd0
  • .sda
  • .sdf
  • .sh
  • .shp
  • .shx
  • .sid
  • .sidd
  • .sidn
  • .sie
  • .sis
  • .sl2
  • .sl3
  • .sldm
  • .sldx
  • .slk
  • .slm
  • .sln
  • .snt
  • .snx
  • .spp
  • .sqb
  • .sql
  • .sqlite
  • .sqlite3
  • .sqlitedb
  • .sqr
  • .sr2
  • .srf
  • .srt
  • .srw
  • .ssq
  • .st4
  • .st5
  • .st6
  • .st7
  • .st8
  • .stc
  • .std
  • .sti
  • .stm
  • .stp
  • .stw
  • .stx
  • .sum
  • .suo
  • .svg
  • .swf
  • .sxc
  • .sxd
  • .sxg
  • .sxi
  • .sxm
  • .sxw
  • .syncdb
  • .t12
  • .t13
  • .tar
  • .tax
  • .tbk
  • .tcf
  • .tex
  • .tga
  • .tgz
  • .thm
  • .tib
  • .tif
  • .tiff
  • .tlg
  • .tmd
  • .tmp
  • .tor
  • .trn
  • .txt
  • .ub
  • .uop
  • .uot
  • .upk
  • .vb
  • .vbk
  • .vbm
  • .vbox
  • .vbs
  • .vcd
  • .vcf
  • .vdf
  • .vdi
  • .vfs0
  • .vhd
  • .vhdx
  • .vib
  • .vlb
  • .vmdk
  • .vmem
  • .vmsd
  • .vmx
  • .vmxf
  • .vob
  • .vom
  • .vpk
  • .vpp_pc
  • .vsd
  • .vsdx
  • .vtf
  • .w3x
  • .wab
  • .wad
  • .wallet
  • .wav
  • .wb2
  • .wbk
  • .wdb
  • .wk1
  • .wks
  • .wma
  • .wmo
  • .wmv
  • .wotreplay
  • .wpd
  • .wps
  • .x11
  • .x3f
  • .xf
  • .xg3
  • .xgo
  • .xis
  • .xla
  • .xlam
  • .xlc
  • .xlk
  • .xlm
  • .xlr
  • .xls
  • .xlsb
  • .xlsm
  • .xlsx
  • .xlt
  • .xltm
  • .xltx
  • .xlw
  • .xml
  • .xps
  • .xslt
  • .xxx
  • .yb2
  • .ycbcra
  • .ydk
  • .zip
  • .zpd
  • .ztmp

It does the following:

  • It affects all existing drives in the system
  • It encrypts files from network shares

Ransomware Routine

This Ransomware encrypts files found in the following folders:

  • Program Files\Microsoft\Exchange Server
  • Program Files (x86)\Microsoft\Exchange Server
  • Program Files\Microsoft SQL Server
  • Program Files (x86)\Microsoft SQL Server

It avoids encrypting files found in the following folders:

  • %All Users Profile%
  • %User Profile%\AppData
  • %Windows%
  • %Program Files%
  • %System Root%
  • \intel
  • \nvidia

(Note: %All Users Profile% is the common user's profile folder, which is usually C:\Documents and Settings\All Users on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\ProgramData on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit). . %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name} on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).. %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.. %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000(32-bit), Server 2003(32-bit), XP, Vista(64-bit), 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit) , or C:\Program Files (x86) in Windows XP(64-bit), Vista(64-bit), 7(64-bit), 8(64-bit), 8.1(64-bit), 2008(64-bit), 2012(64-bit) and 10(64-bit).. %System Root% is the Windows root folder, where it usually is C:\ on all Windows operating system versions.)

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

  • .ReadInstructions

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

  • %Desktop%\Recovery_Instructions.mht
  • %System Root%\Recovery_Instructions.mht
  • {Drive Letter}\Recovery_Instructions.mht

It avoids encrypting files with the following file extensions:

  • .dat
  • .dll
  • .exe
  • .mht
  • .ini
  • .lnk
  • .sys
  • .ReadInstructions

  SOLUTION

Minimum Scan Engine: 9.800
FIRST VSAPI PATTERN FILE: 16.612.08
FIRST VSAPI PATTERN DATE: 23 Mar 2021
VSAPI OPR PATTERN File: 16.613.00
VSAPI OPR PATTERN Date: 24 Mar 2021

Step 1

Trend Micro Predictive Machine Learning detects and blocks malware at the first sign of its existence, before it executes on your system. When enabled, your Trend Micro product detects this malware under the following machine learning name:

     
    • Troj.Win32.TRX.XXPE50FFF042

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

Before doing any scans, Windows 7, Windows 8, Windows 8.1, and Windows 10 users must disable System Restore to allow full scanning of their computers.

Step 4

Restart in Safe Mode

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Step 5

Delete this registry value

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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
    • MSFEEditor = "{Malware file path}\{Malware file name} e"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System
    • EnableLinkedConnections = 1

Step 6

Search and delete this file

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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.
  • %Application Data%\KEY.FILE
  • %Desktop%\Recovery_Instructions.mht
  • %System Root%\Recovery_Instructions.mht
  • {Drive Letter}\Recovery_Instructions.mht

Step 7

Restart in normal mode and scan your computer with your Trend Micro product for files detected as Ransom.Win64.MEDUSALOCKER.AB. 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.


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