Ransom_CRYPRADAM.A
Trojan.Ransomcrypt.W (Symantec), a variant of Win32/Filecoder.NFN (ESET)
Windows
Threat Type: Trojan
Destructiveness: No
Encrypted: Yes
In the wild: Yes
OVERVIEW
This Trojan may be downloaded by other malware/grayware/spyware from remote sites.
It connects to certain websites to send and receive information. It deletes the initially executed copy of itself. It gathers information and reports it to its servers.
TECHNICAL DETAILS
Arrival Details
This Trojan may be downloaded by other malware/grayware/spyware from remote sites.
Installation
This Trojan drops the following copies of itself into the affected system and executes them:
- %Application Data%\{malware filename}.exe
(Note: %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.)
It drops the following files:
- {malware path}\YOUR_FILES.url
It drops the following component file(s):
- {malware path}\aaa.bat - used to delete the initial malware copy
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\Run
{malware filename} = "{malware filename}.exe"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
{malware filename} = "{malware filename}.exe"
Download Routine
This Trojan accesses the following websites to download files:
- http://{BLOCKED}gocash.com/file/build.exe
It saves the files it downloads using the following names:
- %Application Data%\build.exe - updated copy
(Note: %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.)
Other Details
This Trojan connects to the following URL(s) to get the affected system's IP address:
- checkip.dyndns.org
It connects to the following website to send and receive information:
- http://{BLOCKED}gocash.com/mask.php
- http://{BLOCKED}gocash.com/API.php
- http://{BLOCKED}gocash.com/domains.php
It does the following:
- It appends the exention .RRK to encrypted files
- It encrypts files having the following extensions:
- 1cd
- 1st
- 2bp
- 3dm
- 3ds
- 3fr
- 4db
- 4dl
- 4mp
- 73i
- 8xi
- 9png
- a3d
- abm
- abs
- abw
- accdb
- accdc
- accde
- accdr
- accdt
- accdw
- accft
- act
- adn
- adp
- af2
- af3
- aft
- afx
- agif
- agp
- ahd
- ai
- aic
- aim
- albm
- alf
- ani
- ans
- apd
- apm
- apng
- aps
- apt
- apx
- art
- artwork
- arw
- asc
- ascii
- ase
- ask
- asw
- asy
- aty
- avatar
- awdb
- awp
- awt
- aww
- azz
- backup
- bad
- bak
- bay
- bbs
- bdb
- bdp
- bdr
- bean
- bib
- blend
- blkrt
- bm2
- bmp
- bmx
- bmz
- bna
- bnd
- boc
- bok
- brk
- brn
- brt
- bss
- btd
- bti
- btr
- bzabw
- c4
- c4d
- cal
- cals
- can
- cd5
- cdb
- cdc
- cdg
- cdmm
- cdmt
- cdmtz
- cdmz
- cdr
- cdr3
- cdr4
- cdr6
- cdrw
- cdt
- cf
- cfu
- cgm
- chart
- chord
- cimg
- cin
- cit
- ckp
- clkw
- cma
- cmx
- cnm
- cnv
- colz
- cpc
- cpd
- cpg
- cps
- cpt
- cpx
- cr2
- crd
- crwl
- css
- csv
- csy
- ct
- cv5
- cvg
- cvi
- cvs
- cvx
- cwt
- cxf
- cyi
- daconnections
- dacpac
- dad
- dadiagrams
- daf
- daschema
- db
- db-shm
- db-wal
- db2
- db3
- dbc
- dbf
- dbk
- dbs
- dbt
- dbv
- dbx
- dc2
- dca
- dcb
- dcr
- dcs
- dct
- dcx
- ddl
- ddoc
- dds
- ded
- design
- df1
- dgn
- dgs
- dgt
- dhs
- dib
- dicom
- diz
- djv
- djvu
- dm3
- dmi
- dmo
- dnc
- dne
- doc
- docm
- docx
- docxml
- docz
- dot
- dotm
- dotx
- dp1
- dpp
- dpx
- dqy
- drw
- drz
- dsk
- dsn
- dsv
- dt
- dt2
- dta
- dtsx
- dtw
- dvi
- dvl
- dwg
- dx
- dxb
- dxf
- dxl
- eco
- ecw
- ecx
- edb
- efd
- egc
- eio
- eip
- eit
- emd
- emf
- emlx
- ep
- epf
- epp
- eps
- epsf
- eql
- erf
- err
- etf
- etx
- euc
- exr
- fadein
- fal
- faq
- fax
- fb2
- fb3
- fbl
- fbx
- fcd
- fcf
- fdb
- fdf
- fdr
- fds
- fdt
- fdx
- fdxt
- fes
- fft
- fh10
- fh11
- fh3
- fh4
- fh5
- fh6
- fh7
- fh8
- fic
- fid
- fif
- fig
- fil
- flc
- fli
- flr
- fm5
- fmp
- fmp12
- fmpsl
- fmv
- fodt
- fol
- fountain
- fp3
- fp4
- fp5
- fp7
- fpos
- fpt
- fpx
- frt
- ft10
- ft11
- ft7
- ft8
- ft9
- ftn
- fwdn
- fxc
- fxg
- fzb
- fzv
- g3
- gcdp
- gdb
- gdoc
- gdraw
- gem
- geo
- gfb
- gfie
- ggr
- gif
- gih
- gim
- gio
- glox
- gmbck
- gmspr
- gpd
- gpn
- gro
- grob
- grs
- gsd
- gthr
- gtp
- gv
- gwi
- hbk
- hdb
- hdp
- hdr
- hht
- his
- hpg
- hpgl
- hpi
- hpl
- hs
- htc
- html
- hwp
- hz
- i3d
- ib
- icn
- icon
- icpr
- idc
- idea
- idx
- igt
- igx
- ihx
- iil
- iiq
- imd
- info
- ink
- int
- ipf
- ipx
- itc2
- itdb
- itw
- iwi
- j
- j2c
- j2k
- jarvis
- jas
- jb2
- jbig
- jbig2
- jbmp
- jbr
- jfif
- jia
- jis
- jng
- joe
- jp1
- jp2
- jpe
- jpeg
- jpg
- jpg2
- jps
- jpx
- jrtf
- jtf
- jtx
- jwl
- jxr
- kdb
- kdbx
- kdc
- kdi
- kdk
- kes
- kic
- klg
- knt
- kon
- kpg
- kwd
- latex
- lbm
- lbt
- lgc
- lis
- lit
- ljp
- lmk
- lnt
- lp2
- lrc
- lst
- ltr
- ltx
- lue
- luf
- lwo
- lwp
- lws
- lxfml
- lyt
- lyx
- m3d
- ma
- mac
- man
- map
- maq
- mat
- max
- mb
- mbm
- mbox
- md5txt
- mdb
- mdbhtml
- mdf
- mdn
- mdt
- me
- mef
- mell
- mft
- mgcb
- mgmf
- mgmt
- mgmx
- mgtx
- min
- mmat
- mng
- mnr
- mnt
- mobi
- mos
- movie.byu
- mpf
- mpo
- mrg
- mrxs
- msg
- mt9
- mud
- mwb
- mwp
- mxl
- myd
- myl
- ncr
- nct
- ndf
- nfo
- njx
- nlm
- notes
- now
- nrw
- ns2
- ns3
- ns4
- nsf
- nv2
- nwctxt
- nyf
- nzb
- obj
- oc3
- oc4
- oc5
- oce
- oci
- ocr
- odb
- odm
- odo
- ods
- odt
- ofl
- oft
- omf
- openbsd
- oplc
- oqy
- ora
- orf
- ort
- orx
- ota
- otg
- oti
- ott
- ovp
- ovr
- owc
- owg
- oyx
- ozb
- ozj
- ozt
- p7s
- p96
- p97
- pages
- pal
- pan
- pano
- pap
- pbm
- pc1
- pc2
- pc3
- pcd
- pcs
- pcx
- pdb
- pdd
- pdm
- pdn
- pe4
- pef
- pfd
- pff
- pfi
- pfs
- pfv
- pfx
- pgf
- pgm
- phm
- pi1
- pi2
- pi3
- pic
- pict
- pix
- pjpeg
- pjpg
- pjt
- pl
- plantuml
- plt
- pm
- pmg
- png
- pni
- pnm
- pntg
- pnz
- pobj
- pop
- pp4
- pp5
- ppm
- ppt
- pptm
- pptx
- prt
- prw
- ps
- psd
- psdx
- pse
- psid
- psp
- pspbrush
- psw
- ptg
- pth
- ptx
- pu
- pvj
- pvm
- pvr
- pwa
- pwi
- pwr
- px
- pxr
- pz3
- pza
- pzp
- pzs
- qdl
- qmg
- qpx
- qry
- qvd
- rad
- ras
- raw
- rctd
- rcu
- rdb
- rdl
- readme
- rft
- rgb
- rgf
- rib
- ric
- riff
- ris
- rix
- rle
- rli
- rng
- rpd
- rpf
- rpt
- rri
- rs
- rsb
- rsd
- rsr
- rst
- rt
- rtd
- rtf
- rtx
- run
- rw2
- rwl
- rzk
- rzn
- s2mv
- s3m
- saf
- safetext
- sai
- sam
- save
- sbf
- scad
- scc
- sci
- scm
- scriv
- scrivx
- sct
- scv
- scw
- sdb
- sdf
- sdm
- sdoc
- sdw
- sep
- sfc
- sfera
- sfw
- sgm
- sig
- sk1
- sk2
- skcard
- skm
- sla
- slagz
- sld
- sldasm
- slddrt
- sldprt
- sls
- smf
- smil
- sms
- snagitstamps
- snagstyles
- sob
- spa
- spe
- sph
- spj
- spp
- spq
- spr
- sqb
- sql
- sqlite
- sqlite3
- sqlitedb
- sr2
- srw
- ssa
- ssfn
- ssk
- st
- ste
- stm
- stn
- stp
- str
- strings
- stw
- sty
- sub
- sumo
- sva
- svf
- svg
- svgz
- swf
- sxd
- sxg
- sxw
- t2b
- tab
- tb0
- tbn
- tcx
- tdf
- tdt
- te
- teacher
- tex
- text
- tfc
- tg4
- tga
- thm
- thp
- thumb
- tif
- tiff
- tjp
- tlb
- tlc
- tm
- tm2
- tmd
- tmv
- tmx
- tn
- tne
- tpc
- tpi
- trelby
- trm
- tvj
- txt
- u3d
- u3i
- udb
- ufo
- ufr
- uga
- unauth
- unity
- unx
- uof
- uot
- upd
- usertile-ms
- usr
- utf8
- utxt
- v12
- vault
- vbr
- vct
- vda
- vdb
- vec
- vff
- vml
- vnt
- vpd
- vpe
- vrml
- vrp
- vsd
- vsdm
- vsdx
- vsm
- vst
- vstm
- vstx
- vue
- vw
- wb1
- wbc
- wbd
- wbk
- wbm
- wbmp
- wbz
- wcf
- wdb
- wdp
- webdoc
- webp
- wgz
- wire
- wmdb
- wmf
- wn
- wp
- wp4
- wp5
- wp6
- wp7
- wpa
- wpb
- wpd
- wpe
- wpg
- wpl
- wps
- wpt
- wpw
- wri
- wsc
- wsd
- wsh
- wtx
- wvl
- x
- x3d
- x3f
- xar
- xbdoc
- xbplate
- xdb
- xdl
- xhtm
- xld
- xlf
- xlgc
- xls
- xlsm
- xlsx
- xmind
- xmmap
- xpm
- xps
- xwp
- xy3
- xyp
- xyw
- y
- yal
- ybk
- yml
- ysp
- z3d
- zabw
- zdb
- zdc
- zif
- zw
It deletes the initially executed copy of itself
It gathers the following information and reports it to its servers:
- OS version
- IP address
- List of drives
SOLUTION
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
Scan your computer with your Trend Micro product and note files detected as Ransom_CRYPRADAM.A
Step 4
Restart in Safe Mode
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
- {malware filename} = "{malware filename}.exe"
- {malware filename} = "{malware filename}.exe"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
- {malware filename} = "{malware filename}.exe"
- {malware filename} = "{malware filename}.exe"
Step 6
Search and delete this file
- {malware path}\aaa.bat
- %Application Data%\build.exe
- {malware path}\YOUR_FILES.url
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as Ransom_CRYPRADAM.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 8
Restore encrypted files from backup.
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