Analysis by: Homer Pacag

 ALIASES:

Ransom:Win32/Tovicrypt.A (Microsoft)

 PLATFORM:

Windows

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel: Downloaded from the Internet

This ransomware is believed to be patterned after WALTRIX/CRYPTXXX. It almost has the same routines as the aforementioned ransomware family, save for a few minor differences.

To get a one-glance comprehensive view of the behavior of this Trojan, refer to the Threat Diagram shown below.

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.

  TECHNICAL DETAILS

File Size: 254,976 bytes
File Type: DLL
Memory Resident: Yes
Initial Samples Received Date: 07 Jul 2016
Payload: Connects to URLs/IPs, Encrypts files, Displays message/message boxes

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 files:

  • %User Temp%\README.TXT - text ransom note
  • %User Temp%\README.HTML - webpage ransom note
  • %User Temp%\README.BMP - wallpaper/image ransom note
  • %User Temp%\PAB.KEY
  • {folders containing encrypted files}\README.HTML - ransom note
  • {folders containing encrypted files}\README.BMP - ransom note
  • {folders containing encrypted files}\README.TXT - ransom note

(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.)

Autostart Technique

This Trojan drops the following file(s) in the Windows User Startup folder to enable its automatic execution at every system startup:

  • %User Startup%\README.TXT - text ransom note
  • %User Startup%\README.HTML - webpage ransom note
  • %User Startup%\README.BMP - image ransom note

(Note: %User Startup% is the current user's Startup folder, which is usually C:\Documents and Settings\{user}\Start Menu\Programs\Startup on Windows 2000 and XP, and C:\Documents and Settings\{User name}\Start Menu\Programs\Startup on Windows Vista, 7, and 8.)

Other System Modifications

This Trojan modifies the following file(s):

  • It encrypts files and retains original filename and extension

Other Details

This Trojan encrypts files with the following extensions:

  • .3DM
  • .3DS
  • .3G2
  • .3GP
  • .4DB
  • .4DL
  • .4MP
  • .A3D
  • .ABM
  • .ABS
  • .ABW
  • .ACCDB
  • .ACT
  • .ADN
  • .ADP
  • .AES
  • .AF2
  • .AF3
  • .AFT
  • .AFX
  • .AGIF
  • .AGP
  • .AHD
  • .AIC
  • .AIF
  • .AIM
  • .ALBM
  • .ALF
  • .ANI
  • .ANS
  • .APD
  • .APK
  • .APM
  • .APNG
  • .APP
  • .APS
  • .APT
  • .APX
  • .ARC
  • .ART
  • .ARW
  • .ASC
  • .ASE
  • .ASF
  • .ASK
  • .ASM
  • .ASP
  • .ASPX
  • .ASW
  • .ASX
  • .ASY
  • .ATY
  • .AVI
  • .AWDB
  • .AWP
  • .AWT
  • .AWW
  • .AZZ
  • .BAD
  • .BAY
  • .BBS
  • .BDB
  • .BDP
  • .BDR
  • .BEAN
  • .BIB
  • .BM2
  • .BMP
  • .BMX
  • .BNA
  • .BND
  • .BOC
  • .BOK
  • .BRD
  • .BRK
  • .BRN
  • .BRT
  • .BSS
  • .BTD
  • .BTI
  • .BTR
  • .BZ2
  • .C4D
  • .CAL
  • .CALS
  • .CAN
  • .CD5
  • .CDB
  • .CDC
  • .CDG
  • .CDMM
  • .CDMT
  • .CDR
  • .CDR3
  • .CDR4
  • .CDR6
  • .CDT
  • .CER
  • .CFG
  • .CFM
  • .CFU
  • .CGI
  • .CGM
  • .CIMG
  • .CIN
  • .CIT
  • .CKP
  • .CLASS
  • .CLKW
  • .CMA
  • .CMD
  • .CMX
  • .CNM
  • .CNV
  • .COLZ
  • .CPC
  • .CPD
  • .CPG
  • .CPP
  • .CPS
  • .CPT
  • .CPX
  • .CRD
  • .CRT
  • .CRWL
  • .CRYPT
  • .CSR
  • .CSS
  • .CSV
  • .CSY
  • .CUE
  • .CV5
  • .CVG
  • .CVI
  • .CVS
  • .CVX
  • .CWT
  • .CXF
  • .CYI
  • .DAD
  • .DAF
  • .DB3
  • .DBF
  • .DBK
  • .DBT
  • .DBV
  • .DBX
  • .DCA
  • .DCB
  • .DCH
  • .DCS
  • .DCT
  • .DCU
  • .DCX
  • .DDL
  • .DDOC
  • .DDS
  • .DED
  • .DF1
  • .DGN
  • .DGS
  • .DHS
  • .DIB
  • .DIF
  • .DIP
  • .DIZ
  • .DJV
  • .DJVU
  • .DM3
  • .DMI
  • .DMO
  • .DNC
  • .DNE
  • .DOC
  • .DOCB
  • .DOCM
  • .DOCX
  • .DOCZ
  • .DOT
  • .DOTM
  • .DOTX
  • .DP1
  • .DPP
  • .DPX
  • .DQY
  • .DRW
  • .DRZ
  • .DSK
  • .DSN
  • .DSV
  • .DT2
  • .DTA
  • .DTD
  • .DTSX
  • .DTW
  • .DVI
  • .DVL
  • .DWG
  • .DXB
  • .DXF
  • .DXL
  • .ECO
  • .ECW
  • .ECX
  • .EDB
  • .EFD
  • .EGC
  • .EIO
  • .EIP
  • .EIT
  • .EMD
  • .EMF
  • .EML
  • .EMLX
  • .EPF
  • .EPP
  • .EPS
  • .EPSF
  • .EQL
  • .ERF
  • .ERR
  • .ETF
  • .ETX
  • .EUC
  • .EXR
  • .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
  • .FLA
  • .FLI
  • .FLR
  • .FLV
  • .FM5
  • .FMV
  • .FODT
  • .FOL
  • .FP3
  • .FP4
  • .FP5
  • .FP7
  • .FPOS
  • .FPT
  • .FPX
  • .FRM
  • .FRT
  • .FT10
  • .FT11
  • .FT7
  • .FT8
  • .FT9
  • .FTN
  • .FWDN
  • .FXC
  • .FXG
  • .FZB
  • .FZV
  • .GADGET
  • .GBK
  • .GBR
  • .GCDP
  • .GDB
  • .GDOC
  • .GED
  • .GEM
  • .GEO
  • .GFB
  • .GGR
  • .GIF
  • .GIH
  • .GIM
  • .GIO
  • .GLOX
  • .GPD
  • .GPG
  • .GPN
  • .GPX
  • .GRO
  • .GROB
  • .GRS
  • .GSD
  • .GTHR
  • .GTP
  • .GWI
  • .HBK
  • .HDB
  • .HDP
  • .HDR
  • .HHT
  • .HIS
  • .HPG
  • .HPGL
  • .HPI
  • .HPL
  • .HTC
  • .HTM
  • .HTML
  • .HWP
  • .I3D
  • .IBD
  • .IBOOKS
  • .ICN
  • .ICON
  • .IDC
  • .IDEA
  • .IDX
  • .IFF
  • .IGT
  • .IGX
  • .IHX
  • .IIL
  • .IIQ
  • .IMD
  • .INDD
  • .INFO
  • .INI
  • .INI0
  • .INI4
  • .INI8
  • .INID
  • .INIH
  • .INIL
  • .INIP
  • .INIT
  • .INIX
  • .INK
  • .IPF
  • .IPX
  • .ITDB
  • .ITW
  • .IWI
  • .J2C
  • .J2K
  • .JAR
  • .JAS
  • .JAVA
  • .JB2
  • .JBMP
  • .JBR
  • .JFIF
  • .JIA
  • .JIS
  • .JKS
  • .JNG
  • .JOE
  • .JP1
  • .JP2
  • .JPE
  • .JPEG
  • .JPG
  • .JPG2
  • .JPS
  • .JPX
  • .JRTF
  • .JSP
  • .JTX
  • .JWL
  • .JXR
  • .KDB
  • .KDBX
  • .KDC
  • .KDI
  • .KDK
  • .KES
  • .KEY
  • .KIC
  • .KLG
  • .KML
  • .KMZ
  • .KNT
  • .KON
  • .KPG
  • .KWD
  • .LAY
  • .LAY6
  • .LBM
  • .LBT
  • .LDF
  • .LGC
  • .LIS
  • .LIT
  • .LJP
  • .LMK
  • .LNT
  • .LP2
  • .LRC
  • .LST
  • .LTR
  • .LTX
  • .LUA
  • .LUE
  • .LUF
  • .LWO
  • .LWP
  • .LWS
  • .LYT
  • .LYX
  • .M3D
  • .M3U
  • .M4A
  • .M4V
  • .MAC
  • .MAN
  • .MAP
  • .MAQ
  • .MAT
  • .MAX
  • .MBM
  • .MBOX
  • .MDB
  • .MDF
  • .MDN
  • .MDT
  • .MEF
  • .MELL
  • .MFD
  • .MFT
  • .MGCB
  • .MGMT
  • .MGMX
  • .MID
  • .MIN
  • .MKV
  • .MMAT
  • .MML
  • .MNG
  • .MNR
  • .MNT
  • .MOBI
  • .MOS
  • .MOV
  • .MP3
  • .MP4
  • .MPA
  • .MPF
  • .MPG
  • .MPO
  • .MRG
  • .MRXS
  • .MS11
  • .MSG
  • .MSI
  • .MT9
  • .MUD
  • .MWB
  • .MWP
  • .MXL
  • .MYD
  • .MYI
  • .MYL
  • .NCR
  • .NCT
  • .NDF
  • .NEF
  • .NFO
  • .NJX
  • .NLM
  • .NOTE
  • .NOW
  • .NRW
  • .NS2
  • .NS3
  • .NS4
  • .NSF
  • .NV2
  • .NYF
  • .NZB
  • .OBJ
  • .OC3
  • .OC4
  • .OC5
  • .OCE
  • .OCI
  • .OCR
  • .ODB
  • .ODG
  • .ODM
  • .ODO
  • .ODP
  • .ODS
  • .ODT
  • .OFL
  • .OFT
  • .OMF
  • .OPLC
  • .OQY
  • .ORA
  • .ORF
  • .ORT
  • .ORX
  • .OTA
  • .OTG
  • .OTI
  • .OTP
  • .OTS
  • .OTT
  • .OVP
  • .OVR
  • .OWC
  • .OWG
  • .OYX
  • .OZB
  • .OZJ
  • .OZT
  • .P12
  • .P7S
  • .P96
  • .P97
  • .PAGES
  • .PAL
  • .PAN
  • .PANO
  • .PAP
  • .PAQ
  • .PAS
  • .PBM
  • .PC1
  • .PC2
  • .PC3
  • .PCD
  • .PCS
  • .PCT
  • .PCX
  • .PDB
  • .PDD
  • .PDF
  • .PDM
  • .PDN
  • .PDS
  • .PDT
  • .PE4
  • .PEF
  • .PEM
  • .PFF
  • .PFI
  • .PFS
  • .PFV
  • .PFX
  • .PGF
  • .PGM
  • .PHM
  • .PHP
  • .PI1
  • .PI2
  • .PI3
  • .PIC
  • .PICT
  • .PIF
  • .PIX
  • .PJPG
  • .PJT
  • .PLT
  • .PLUGIN
  • .PMG
  • .PNG
  • .PNI
  • .PNM
  • .PNTG
  • .PNZ
  • .POP
  • .POT
  • .POTM
  • .POTX
  • .PP4
  • .PP5
  • .PPAM
  • .PPM
  • .PPS
  • .PPSM
  • .PPSX
  • .PPT
  • .PPTM
  • .PPTX
  • .PRF
  • .PRIV
  • .PRIVATE
  • .PRT
  • .PRW
  • .PSD
  • .PSDX
  • .PSE
  • .PSID
  • .PSP
  • .PSPIMAGE
  • .PSW
  • .PTG
  • .PTH
  • .PTX
  • .PVJ
  • .PVM
  • .PVR
  • .PWA
  • .PWI
  • .PWR
  • .PXR
  • .PZ3
  • .PZA
  • .PZP
  • .PZS
  • .QCOW2
  • .QDL
  • .QMG
  • .QPX
  • .QRY
  • .QVD
  • .RAD
  • .RAR
  • .RAS
  • .RAW
  • .RCTD
  • .RCU
  • .RDB
  • .RDDS
  • .RDL
  • .RFT
  • .RGB
  • .RGF
  • .RIB
  • .RIC
  • .RIFF
  • .RIS
  • .RIX
  • .RLE
  • .RLI
  • .RNG
  • .RPD
  • .RPF
  • .RPT
  • .RRI
  • .RSB
  • .RSD
  • .RSR
  • .RSS
  • .RST
  • .RTD
  • .RTF
  • .RTX
  • .RUN
  • .RW2
  • .RWL
  • .RZK
  • .RZN
  • .S2MV
  • .S3M
  • .SAF
  • .SAI
  • .SAM
  • .SAVE
  • .SBF
  • .SCAD
  • .SCC
  • .SCH
  • .SCI
  • .SCM
  • .SCT
  • .SCV
  • .SCW
  • .SDB
  • .SDF
  • .SDM
  • .SDOC
  • .SDW
  • .SEP
  • .SFC
  • .SFW
  • .SGM
  • .SIG
  • .SITX
  • .SK1
  • .SK2
  • .SKM
  • .SLA
  • .SLD
  • .SLDX
  • .SLK
  • .SLN
  • .SLS
  • .SMF
  • .SMIL
  • .SMS
  • .SOB
  • .SPA
  • .SPE
  • .SPH
  • .SPJ
  • .SPP
  • .SPQ
  • .SPR
  • .SQB
  • .SQL
  • .SQLITE3
  • .SQLITEDB
  • .SR2
  • .SRT
  • .SRW
  • .SSA
  • .SSK
  • .STC
  • .STD
  • .STE
  • .STI
  • .STM
  • .STN
  • .STP
  • .STR
  • .STW
  • .STY
  • .SUB
  • .SUMO
  • .SVA
  • .SVF
  • .SVG
  • .SVGZ
  • .SWF
  • .SXC
  • .SXD
  • .SXG
  • .SXI
  • .SXM
  • .SXW
  • .T2B
  • .TAB
  • .TAR
  • .TB0
  • .TBK
  • .TBN
  • .TCX
  • .TDF
  • .TDT
  • .TEX
  • .TEXT
  • .TFC
  • .TG4
  • .TGA
  • .TGZ
  • .THM
  • .THP
  • .TIF
  • .TIFF
  • .TJP
  • .TLB
  • .TLC
  • .TM2
  • .TMD
  • .TMP
  • .TMV
  • .TMX
  • .TNE
  • .TPC
  • .TPI
  • .TRM
  • .TVJ
  • .TXT
  • .U3D
  • .U3I
  • .UDB
  • .UFO
  • .UFR
  • .UGA
  • .UNX
  • .UOF
  • .UOP
  • .UOT
  • .UPD
  • .USR
  • .UTF8
  • .UTXT
  • .V12
  • .VBR
  • .VBS
  • .VCF
  • .VCT
  • .VCXPROJ
  • .VDA
  • .VDB
  • .VDI
  • .VEC
  • .VFF
  • .VMDK
  • .VML
  • .VMX
  • .VNT
  • .VOB
  • .VPD
  • .VPE
  • .VRML
  • .VRP
  • .VSD
  • .VSDM
  • .VSDX
  • .VSM
  • .VST
  • .VSTX
  • .VUE
  • .WAV
  • .WB1
  • .WBC
  • .WBD
  • .WBK
  • .WBM
  • .WBMP
  • .WBZ
  • .WCF
  • .WDB
  • .WDP
  • .WEBP
  • .WGZ
  • .WIRE
  • .WKS
  • .WMA
  • .WMDB
  • .WMF
  • .WMV
  • .WP4
  • .WP5
  • .WP6
  • .WP7
  • .WPA
  • .WPD
  • .WPE
  • .WPG
  • .WPL
  • .WPS
  • .WPT
  • .WPW
  • .WRI
  • .WSC
  • .WSD
  • .WSF
  • .WSH
  • .WTX
  • .WVL
  • .X3D
  • .X3F
  • .XAR
  • .XCODEPROJ
  • .XDB
  • .XDL
  • .XHTM
  • .XHTML
  • .XLC
  • .XLD
  • .XLF
  • .XLGC
  • .XLM
  • .XLR
  • .XLS
  • .XLSB
  • .XLSM
  • .XLSX
  • .XLT
  • .XLTM
  • .XLTX
  • .XLW
  • .XML
  • .XPM
  • .XPS
  • .XWP
  • .XY3
  • .XYP
  • .XYW
  • .YAL
  • .YBK
  • .YML
  • .YSP
  • .YUV
  • .Z3D
  • .ZABW
  • .ZDB
  • .ZDC
  • .ZIF
  • .ZIP
  • .ZIPX
  • .ZZ

It does the following:

  • It deletes shadow copies using vssadmin.exe

NOTES:

This malware sets the system's desktop wallpaper to the following:

The ransom note README.html contains the following:

The ransom note README.txt contains the following:

  SOLUTION

Minimum Scan Engine: 9.800
FIRST VSAPI PATTERN FILE: 12.636.04
FIRST VSAPI PATTERN DATE: 07 Jul 2016
VSAPI OPR PATTERN File: 12.637.00
VSAPI OPR PATTERN Date: 07 Jul 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

Restart in Safe Mode

[ Learn More ]

Step 4

Delete this registry key

[ Learn More ]

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\Control Panel\Desktop
    • Wallpaper = %User Temp%\README.BMP

Step 5

Search and delete this file

[ 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%\PAB.KEY
  • README.TXT
  • README.HTML
  • README.BMP

Step 6

Restart in normal mode and scan your computer with your Trend Micro product for files detected as RANSOM_CRYPMIC.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 7

Scan your computer with your Trend Micro product to delete files detected as RANSOM_CRYPMIC.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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