RANSOM_CRYPSAM.D

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It deletes the initially executed copy of itself.

Arrival Details

This Trojan 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 Trojan drops the following component file(s):

• {root drive}\HELP_DECRYPT_YOUR_FILES.html
• %Desktop%\HELP_DECRYPT_YOUR_FILES.html
• {folders containing encrypted files}\HELP_DECRYPT_YOUR_FILES.html

(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 drops and executes the following files:

• {malware path}\selfdel.exe - used to delete the malware
• {malware path}\del.exe - legitimate Sysinternals SDelete program. The following command is executed to wipe free space on the disk to prevent recovery:

  {malware path}\del.exe -c C: /accepteula

File Infection

This Trojan avoids infecting folders containing the following strings:

• "Windows"
• "Reference Assemblies\Microsoft"
• "Recycle.bin"

Other Details

This Trojan encrypts files with the following extensions:

• .3dm
• .3ds
• .3fr
• .3g2
• .3gp
• .3pr
• .7z
• .ab4
• .accdb
• .accde
• .accdr
• .accdt
• .ach
• .acr
• .act
• .adb
• .ads
• .agdl
• .ai
• .aif
• .aifc
• .aiff
• .ait
• .al
• .apj
• .arw
• .asf
• .asm
• .asp
• .aspx
• .asx
• .au
• .avi
• .awg
• .back
• .backup
• .backupdb
• .bak
• .bank
• .bay
• .bdb
• .bgt
• .bik
• .bkf
• .bkp
• .blend
• .bmp
• .bpw
• .c
• .cdf
• .cdr
• .cdr3
• .cdr4
• .cdr5
• .cdr6
• .cdrw
• .cdx
• .ce1
• .ce2
• .cer
• .cfp
• .cgm
• .cib
• .class
• .cls
• .cmt
• .cpi
• .cpp
• .cr2
• .craw
• .crt
• .crw
• .cs
• .csh
• .csl
• .csv
• .dac
• .db
• .db3
• .dbf
• .db-journal
• .dbx
• .dc2
• .dcr
• .dcs
• .ddd
• .ddoc
• .ddrw
• .dds
• .der
• .des
• .design
• .dgc
• .dib
• .djvu
• .dng
• .doc
• .docm
• .docx
• .dot
• .dotm
• .dotx
• .drf
• .drw
• .dtd
• .dvr-ms
• .dwg
• .dxb
• .dxf
• .dxg
• .emf
• .eml
• .eps
• .erbsql
• .erf
• .exf
• .fdb
• .ffd
• .fff
• .fh
• .fhd
• .fla
• .flac
• .flv
• .fmb
• .fpx
• .fxg
• .gif
• .gray
• .grey
• .gry
• .h
• .hbk
• .hpp
• .hta
• .htm
• .html
• .ibank
• .ibd
• .ibz
• .ico
• .idx
• .iif
• .iiq
• .incpas
• .indd
• .IVF
• .jar
• .java
• .jfif
• .jpe
• .jpeg
• .jpg
• .jsp
• .kbx
• .kc2
• .kdbx
• .kdc
• .key
• .kpdx
• .lua
• .m
• .m1v
• .m3u
• .m4v
• .max
• .mdb
• .mdc
• .mdf
• .mef
• .mfw
• .mid
• .midi
• .mmw
• .moneywell
• .mos
• .mov
• .mp2
• .mp2v
• .mp3
• .mp4
• .mpa
• .mpe
• .mpeg
• .mpg
• .mpv2
• .mrw
• .msg
• .myd
• .nd
• .ndd
• .nef
• .nk2
• .nop
• .nrw
• .ns2
• .ns3
• .ns4
• .nsd
• .nsf
• .nsg
• .nsh
• .nwb
• .nx2
• .nxl
• .nyf
• .oab
• .obj
• .odb
• .odc
• .odf
• .odg
• .odm
• .odp
• .ods
• .odt
• .oil
• .orf
• .ost
• .otg
• .oth
• .otp
• .ots
• .ott
• .p12
• .p7b
• .p7c
• .pab
• .pages
• .pas
• .pat
• .pbl
• .pbl
• .pcd
• .pct
• .pdb
• .pdd
• .pdf
• .pef
• .pem
• .pfx
• .php
• .php5
• .phtml
• .pl
• .plc
• .png
• .pot
• .potm
• .potx
• .ppam
• .pps
• .ppsm
• .ppsx
• .ppt
• .pptm
• .pptx
• .prf
• .ps
• .psafe3
• .psd
• .pspimage
• .pst
• .ptx
• .py
• .qba
• .qbb
• .qbm
• .qbr
• .qbw
• .qbx
• .qby
• .r3d
• .raf
• .rar
• .rat
• .raw
• .rdb
• .rle
• .rm
• .rmi
• .rtf
• .rw2
• .rwl
• .rwz
• .s3db
• .sas7bdat
• .say
• .sd0
• .sda
• .sdf
• .sldm
• .sldx
• .snd
• .sql
• .sqlite
• .sqlite3
• .sqlitedb
• .sr2
• .srf
• .srt
• .srw
• .st4
• .st5
• .st6
• .st7
• .st8
• .std
• .sti
• .stw
• .stx
• .svg
• .swf
• .sxc
• .sxd
• .sxg
• .sxi
• .sxm
• .sxw
• .tex
• .tga
• .thm
• .tib
• .tif
• .tif
• .tiff
• .tlg
• .txt
• .vob
• .wallet
• .war
• .wav
• .wax
• .wb2
• .wm
• .wma
• .wmf
• .wmv
• .wmx
• .wpd
• .wps
• .wvx
• .x11
• .x3f
• .xis
• .xla
• .xlam
• .xlk
• .xlm
• .xlr
• .xls
• .xlsb
• .xlsm
• .xlsx
• .xlt
• .xltm
• .xltx
• .xlw
• .xml
• .ycbcra
• .yuv
• .zip

It does the following:

• It appends the extension .encryptedRSA to the encrypted files
• Uses Bitcoin Address: 1FpZFUGqAkyjAGVgHXhaHrSmThJHxd2a7v
• Uses C2 server https://www.{BLOCKED}e.com/Blog/pikasoart

It deletes the initially executed copy of itself

NOTES:

The dropped HELP_DECRYPT_YOUR_FILES.html contains the following ransom note: