RANSOM_ROKKU.A
Windows
Threat Type: Trojan
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
Spammed via email
This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users.
TECHNICAL DETAILS
681,984 bytes
EXE
No
21 Mar 2016
Encrypts files
Arrival Details
This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users.
Installation
This Trojan drops the following files:
- {root drive}\README_HOW_TO_UNLOCK.TXT
- {root drive}\README_HOW_TO_UNLOCK.HTML
- {folders containing encrypted files}\README_HOW_TO_UNLOCK.TXT
- {folders containing encrypted files}\README_HOW_TO_UNLOCK.HTML
- %Start Menu%\Programs\Startup\README_HOW_TO_UNLOCK.TXT
- %Start Menu%\Programs\Startup\README_HOW_TO_UNLOCK.HTML
(Note: %Start Menu% is the Start Menu folder, where it usually is C:\Documents and Settings\{user name}\Start Menu on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming\Microsoft\Windows\Start Menu 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.)
It leaves text files that serve as ransom notes containing the following:
Other System Modifications
This Trojan modifies the following file(s):
- change the encrypted file's extension to ".rokku"
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".)
File Infection
This Trojan avoids infecting folders containing the following strings:
- recycle bin
- system volume information
Process Termination
This Trojan terminates the following services if found on the affected system:
- vss
- swprv
- srservice
Other Details
This Trojan encrypts files with the following extensions:
- 001
- 1dc
- 3ds
- anim
- apk
- arch00
- ari
- art
- arw
- asc
- ase
- asef
- asp
- aspx
- asset
- avi
- bak
- bar
- bay
- bc6
- bc7
- bgeo
- big
- bik
- bkf
- bkp
- blob
- bmp
- bsa
- c4d
- cap
- cas
- catpart
- catproduct
- cdr
- cef
- cer
- cfr
- cgm
- cha
- chr
- cld
- clx
- cpp
- cr2
- crt
- crw
- cs
- css
- csv
- cxx
- d3dbsp
- das
- dat
- dat
- dayzprofile
- dazip
- db
- dbf
- dbfv
- dcr
- dcs
- der
- desc
- dib
- dlc
- dle
- dlv
- dlv3
- dlv4
- dmp
- dng
- doc
- docm
- docx
- drf
- dvi
- dvr
- dwf
- dwg
- dxf
- dxg
- eip
- emf
- emz
- epf
- epk
- eps
- eps2
- eps3
- epsf
- epsp
- erf
- esm
- fbx
- ff
- fff
- fh10
- fh11
- fh7
- fh8
- fh9
- fig
- fsh
- ft8
- fxg
- gdb
- ge2
- gho
- gz
- hip
- hipnc
- hkdb
- hkx
- hplg
- hpp
- hvpl
- hxx
- iam
- ibank
- icb
- icxs
- idea
- iff
- iiq
- indd
- ipt
- iros
- irs
- rw2
- rwl
- rwz
- sav
- sbx
- sc2save
- sdf
- shp
- sid
- sidn
- sie
- sis
- skl
- skp
- sldasm
- sldprt
- slm
- slx
- slxp
- snx
- soft
- sqlite
- sqlite3
- sr2
- srf
- srw
- step
- stl
- stp
- sum
- svg
- svgz
- swatch
- syncdb
- t12
- t13
- tar
- xvc
- xvz
- xxx
- ycbcra
- yuv
- zdct
- zip
- ztmp
- flt
- flv
- fmod
- forge
- fos
- fpk
- itdb
- itl
- itm
- iwd
- iwi
- j2k
- java
- jpe
- jpeg
- jpf
- jpg
- jpx
- k25
- kdb
- kdc
- kf
- kys
- lbf
- lex
- litemod
- lrf
- ltx
- lvl
- m2
- m2t
- m2ts
- m3u
- m4a
- m4v
- ma
- map
- mat
- max
- mb
- mcfi
- mcfp
- mcgame
- mcmeta
- mdb
- mdbackup
- mdc
- mddata
- mdf
- mdl
- mdlp
- mef
- mel
- menu
- mkv
- mll
- mlx
- mn
- mos
- mp
- mp4
- mrw
- mrwref
- mts
- mu
- mxf
- nb
- ncf
- nef
- nrw
- ntl
- obm
- ocdc
- odb
- odc
- odm
- odp
- ods
- odt
- omeg
- orf
- ott
- p12
- p7b
- p7c
- pak
- pct
- pcx
- pdd
- pef
- pem
- pfx
- php
- php4
- php5
- pic
- picnc
- pkpass
- png
- ppd
- ppt
- pptm
- pptx
- prj
- prt
- prtl
- ps
- psb
- psd
- psf
- psid
- psq
- pst
- ptl
- ptx
- pwl
- pxn
- pxr
- py
- qdf
- qic
- r3d
- raa
- raf
- rar
- raw
- rb
- re4
- rgss3a
- rim
- rofl
- rtf
- rtg
- rvt
- tax
- tex
- tga
- tif
- tiff
- tor
- txt
- unity3d
- uof
- uos
- upk
- vda
- vdf
- vfl
- vfs0
- vpk
- vpp_pc
- vst
- vtf
- w3x
- wallet
- wav
- wb2
- wdx
- wma
- wmo
- wmv
- wotreplay
- wpd
- wps
- x3f
- xf
- xl
- xlk
- xlsb
- xlsm
- xlsx
NOTES:
This ransomware executes the following command to delete shadow copies:
wmic.exe shadowcopy delete /nointeractive
vssadmin.exe delete shadows /all/quiet
SOLUTION
9.800
12.416.07
21 Mar 2016
12.417.00
22 Mar 2016
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
Restore this modified 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_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\SystemRestore
- DisableSR = "1"
- DisableSR = "1"
Step 4
Search and delete this file
- README_HOW_TO_UNLOCK.TXT
- README_HOW_TO_UNLOCK.HTML
Step 5
Scan your computer with your Trend Micro product to delete files detected as RANSOM_ROKKU.A. 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 6
Restore encrypted files from backup.
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