RANSOM_HIDDENTEARMOON.A

 Analysis by: Wilbert Vidal

 ALIASES:

Trojan.Ransom.MoonCryptor (ALYac); Ransom:MSIL/Ryzerlo.A (Microsoft);

 PLATFORM:

Windows

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

  • Threat Type: Ransomware

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Dropped by other malware, 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 connects to certain websites to send and receive information. However, as of this writing, the said sites are inaccessible. It is capable of encrypting files in the affected system.

It drops files as ransom note.

  TECHNICAL DETAILS

File Size:

35,328 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

17 Aug 2017

Payload:

Connects to URLs/IPs, Drops files, Encrypts files

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 file(s)/component(s):

  • %Malware Path%\log.cmoon
  • %Malware Path%\l.cmoon
  • %Malware Path%\e.cmoon
  • %Malware Path%\u.cmoon

Autostart Technique

This Ransomware modifies the following registry entries to ensure it automatic execution at every system startup:

HKCU\Software\Microsoft\
Windows\CurrentVersion\Run
moon = {Malware Path}\{Malware Name}

Other System Modifications

This Ransomware sets the system's desktop wallpaper to the following image:

  • (The said site where the wallpaper will be downloaded is inaccessible.)

Download Routine

This Ransomware connects to the following URL(s) to download its component file(s):

  • http://{BLOCKED}.{BLOCKED}.3.1/demand/imggenerator.php

It saves the files it downloads using the following names:

  • %Desktop%\wallpaper.jpg

(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.)

Other Details

This Ransomware connects to the following website to send and receive information:

  • http://{BLOCKED}.{BLOCKED}.3.1/panel/decipher.php

It encrypts files with the following extensions:

  • .zip
  • .7z
  • .rar
  • .m4a
  • .wma
  • .avi
  • .wmv
  • .csv
  • .d3dbsp
  • .sc2save
  • .sie
  • .sum
  • .ibank
  • .t13
  • .t12
  • .qdf
  • .gdb
  • .tax
  • .pkpass
  • .bc6
  • .bc7
  • .bkp
  • .qic
  • .bkf
  • .sidn
  • .sidd
  • .mddata
  • .itl
  • .itdb
  • .icxs
  • .hvpl
  • .hplg
  • .hkdb
  • .mdbackup
  • .syncdb
  • .gho
  • .cas
  • .svg
  • .map
  • .wmo
  • .itm
  • .sb
  • .fos
  • .mcgame
  • .vdf
  • .ztmp
  • .sis
  • .sid
  • .ncf
  • .menu
  • .layout
  • .dmp
  • .blob
  • .esm
  • .001
  • .vtf
  • .dazip
  • .fpk
  • .mlx
  • .kf
  • .iwd
  • .vpk
  • .tor
  • .psk
  • .rim
  • .w3x
  • .fsh
  • .ntl
  • .arch00
  • .lvl
  • .snx
  • .cfr
  • .ff
  • .vpp_pc
  • .lrf
  • .m2
  • .mcmeta
  • .vfs0
  • .mpqge
  • .kdb
  • .db0
  • .DayZProfile
  • .rofl
  • .hkx
  • .bar
  • .upk
  • .das
  • .iwi
  • .litemod
  • .asset
  • .forge
  • .ltx
  • .bsa
  • .apk
  • .re4
  • .sav
  • .lbf
  • .slm
  • .bik
  • .epk
  • .rgss3a
  • .pak
  • .big
  • .unity3d
  • .wotreplay
  • .xxx
  • .desc
  • .py
  • .m3u
  • .flv
  • .js
  • .css
  • .rb
  • .gif
  • .png
  • .jpeg
  • .txt
  • .p7c
  • .p7b
  • .p12
  • .pfx
  • .pem
  • .crt
  • .cer
  • .der
  • .x3f
  • .srw
  • .pef
  • .ptx
  • .r3d
  • .rw2
  • .rwl
  • .raw
  • .raf
  • .orf
  • .nrw
  • .mrwref
  • .mef
  • .erf
  • .kdc
  • .dcr
  • .cr2
  • .crw
  • .bay
  • .sr2
  • .srf
  • .arw
  • .3fr
  • .dng
  • .jpeg
  • .jpg
  • .cdr
  • .indd
  • .ai
  • .eps
  • .pdf
  • .pdd
  • .psd
  • .dbfv
  • .mdf
  • .wb2
  • .rtf
  • .wpd
  • .dxg
  • .xf
  • .dwg
  • .pst
  • .accdb
  • .mdb
  • .pptm
  • .pptx
  • .ppt
  • .xlk
  • .xlsb
  • .xlsm
  • .xlsx
  • .xls
  • .wps
  • .docm
  • .mp3
  • .docx
  • .doc
  • .odb
  • .odc
  • .odm
  • .odp
  • .ods
  • .odt
  • .txt
  • .doc
  • .docx
  • .xls
  • .xlsx
  • .ppt
  • .pptx
  • .odt
  • .jpg
  • .png
  • .wmv
  • .mp4
  • .sql
  • .mdb
  • .php
  • .asp
  • .aspx
  • .html
  • .psd
  • .xml

It does the following:

  • This Ransomware connects to the following malicious URL to create and send encryption keys:
    • http://{BLOCKED}.{BLOCKED}.3.1/panel/createkeys.php
    • http://{BLOCKED}.{BLOCKED}.3.1/panel/savekey.php

However, as of this writing, the said sites are inaccessible.

It is capable of encrypting files in the affected system.

Ransomware Routine

This Ransomware appends the following extension to the file name of the encrypted files:

  • {Encrypted File Name}.fmoon

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

  • {folders containing encrypted files}\_readmyransom.txt

NOTES:
This Ransomware encrypts the file names of the encrypted files with the following keys:

  • "&Vâ5hWBtEû$M§K,jgêd_ç9`^@]}aN.3üGî€CZö%X'(-J² P¨£ëÿbn~vizLqyà)=cµwï2ôéIH4e!U;us7Rxkè6ATOùf¤DF0°+Yop^8r#{[lmQS1ä"
  • It displays the following as ransom note:

    Drop text files:

      SOLUTION

    Minimum Scan Engine:

    9.850

    FIRST VSAPI PATTERN FILE:

    13.600.08

    FIRST VSAPI PATTERN DATE:

    17 Aug 2017

    VSAPI OPR PATTERN File:

    13.601.00

    VSAPI OPR PATTERN Date:

    18 Aug 2017

    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

    Restore this modified registry value

    [ 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\Software\Microsoft\Windows\CurrentVersion\Run
      • moon = {Malware Path}\{Malware Name}

    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.
    • %Malware Path%\e.cmoon
    • %Malware Path%\u.cmoon
    • %Malware Path%\log.cmoon
    • %Malware Path%\l.cmoon
    • {folders containing encrypted files}\_readmyransom.txt

    Step 6

    Reset your Desktop properties

    [ Learn More ]

    Step 7

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

    Step 9

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


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