TROJ_CRILOCK.YNE


 ALIASES:

Ransom:Win32/Crilock.D (Microsoft), Trojan-Ransom.Win32.Crypren.qan (Kaspersky)

 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, Dropped by other malware

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 connects to certain websites to send and receive information.

  TECHNICAL DETAILS

File Size:

229,376 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

16 Sep 2014

Payload:

Encrypts files, Collects system information

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):

  • %ProgramData%\{random folder name}\02000000 - contains path of malware copy
  • %ProgramData%\{random folder name}\00000000 - contains a character

(Note: %ProgramData% is a version of the Program Files folder where any user on a multi-user computer can make changes to programs. This is usually C:\ProgramData in Windows Vista and 7, or C:\Program Files on Windows 2000, XP (32-bit), and Server 2003, or C:\Program Files (x86) on Windows XP (64-bit).)

It drops the following copies of itself into the affected system:

  • %Windows%\{random filename}.exe
  • %ProgramData%\{random folder name}\01000000

(Note: %Windows% is the Windows folder, which is usually C:\Windows.. %ProgramData% is a version of the Program Files folder where any user on a multi-user computer can make changes to programs. This is usually C:\ProgramData in Windows Vista and 7, or C:\Program Files on Windows 2000, XP (32-bit), and Server 2003, or C:\Program Files (x86) on Windows XP (64-bit).)

It adds the following processes:

  • explorer.exe

It injects codes into the following process(es):

  • explorer.exe

Autostart Technique

This Trojan adds the following registry entries to enable its automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
{random name} = "%Windows%\{random filename}.exe"

Other System Modifications

This Trojan adds the following registry entries:

HKEY_CURRENT_USER\Software\{random name}
02000000 = "%Windows%\{random filename}.exe"

HKEY_CURRENT_USER\Software\{random name}
01000000 = "{binary copy of itself}"

Information Theft

This Trojan gathers the following data:

  • Machine GUID
  • Computer name

Other Details

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

  • https://{BLOCKED}anpride.net/gate.php

NOTES:

However, as of this writing, there was no response from the server.

It encrypts the following files and appends ".encrypted" to them:

  • wb2
  • psd
  • p7c
  • p7b
  • p12
  • pfx
  • pem
  • crt
  • cer
  • der
  • pl
  • py
  • lua
  • css
  • js
  • asp
  • php
  • incpas
  • asm
  • hpp
  • cpp
  • 7z
  • zip
  • rar
  • drf
  • blend
  • apj
  • 3ds
  • dwg
  • sda
  • ps
  • pat
  • fxg
  • fhd
  • fh
  • dxb
  • drw
  • design
  • ddrw
  • ddoc
  • dcs
  • csl
  • csh
  • cpi
  • cgm
  • cdx
  • cdrw
  • cdr6
  • cdr5
  • cdr4
  • cdr3
  • cdr
  • awg
  • ait
  • ai
  • agd1
  • ycbcra
  • x3f
  • stx
  • st8
  • st7
  • st6
  • st5
  • st4
  • srw
  • srf
  • sr2
  • sd1
  • sd0
  • rwz
  • rwl
  • rw2
  • raw
  • raf
  • ra2
  • ptx
  • pef
  • pcd
  • orf
  • nwb
  • nrw
  • nop
  • nef
  • ndd
  • mrw
  • mos
  • mfw
  • mef
  • mdc
  • kdc
  • kc2
  • iiq
  • gry
  • grey
  • gray
  • fpx
  • fff
  • exf
  • erf
  • dng
  • dcr
  • dc2
  • crw
  • craw
  • cr2
  • cmt
  • cib
  • ce2
  • ce1
  • arw
  • 3pr
  • 3fr
  • mpg
  • jpeg
  • jpg
  • mdb
  • sqlitedb
  • sqlite3
  • sqlite
  • sql
  • sdf
  • sav
  • sas7bdat
  • s3db
  • rdb
  • psafe3
  • nyf
  • nx2
  • nx1
  • nsh
  • nsg
  • nsf
  • nsd
  • ns4
  • ns3
  • ns2
  • myd
  • kpdx
  • kdbx
  • idx
  • ibz
  • ibd
  • fdb
  • erbsql
  • db3
  • dbf
  • db-journal
  • db
  • cls
  • bdb
  • al
  • adb
  • backupdb
  • bik
  • backup
  • bak
  • bkp
  • moneywell
  • mmw
  • ibank
  • hbk
  • ffd
  • dgc
  • ddd
  • dac
  • cfp
  • cdf
  • bpw
  • bgt
  • acr
  • ac2
  • ab4
  • djvu
  • pdf
  • sxm
  • odf
  • std
  • sxd
  • otg
  • sti
  • sxi
  • otp
  • odg
  • odp
  • stc
  • sxc
  • ots
  • ods
  • sxg
  • stw
  • sxw
  • odm
  • oth
  • ott
  • odt
  • odb
  • csv
  • rtf
  • accdr
  • accdt
  • accde
  • accdb
  • sldm
  • sldx
  • ppsm
  • ppsx
  • ppam
  • potm
  • potx
  • pptm
  • pptx
  • pps
  • pot
  • ppt
  • xlw
  • xll
  • xlam
  • xla
  • xlsb
  • xltm
  • xltx
  • xlsm
  • xlsx
  • xlm
  • xlt
  • xls
  • xml
  • dotm
  • dotx
  • docm
  • docx
  • dot
  • doc
  • txt

After successfully encrypting user's files, it drops the ransom note DECRYPT_INSTRUCTIONS.html.

It deletes shadow copies by executing the following command:

  • vssadmin.exe Delete Shadows /All /Quiet

  SOLUTION

Minimum Scan Engine:

9.700

FIRST VSAPI PATTERN FILE:

11.156.05

FIRST VSAPI PATTERN DATE:

18 Sep 2014

VSAPI OPR PATTERN File:

11.157.00

VSAPI OPR PATTERN Date:

19 Sep 2014

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

Scan your computer with your Trend Micro product and note files detected as TROJ_CRILOCK.YNE

Step 3

Restart in Safe Mode

[ Learn More ]

Step 4

Delete this 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_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    • {random name} = "%Windows%\{random filename}.exe"
  • In HKEY_CURRENT_USER\Software\{random name}
    • 02000000 = "%Windows%\{random filename}.exe"
  • In HKEY_CURRENT_USER\Software\{random name}
    • 01000000 = "{binary copy of itself}"

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.
  • DECRYPT_INSTRUCTIONS.html

Step 6

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