➔
search
✕

Ransom_CRYPCHIM.CE

March 05, 2019
 Analysis by: Henry Alarcon Jr.
 ALIASES:

Ransom:Win32/Vigorf.A (Microsoft), Trojan-Ransom.Win32.Chimera.a (Kaspersky), Win32.Trojan-Ransom.Chimera.A (GData)

 PLATFORM:

Windows

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

  • Threat Type: Ransomware

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Downloaded from the Internet, Dropped by other malware


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.

It encrypts files with specific file extensions. It drops files as ransom note.

  TECHNICAL DETAILS

File Size:

74,620 bytes

File Type:

EXE

File Compression:

Petite

Memory Resident:

No

Initial Samples Received Date:

01 Oct 2018

Payload:

Encrypts files, Compromises system security, Steals information, Downloads 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 adds the following processes:

  • iexplore.exe

It adds the following mutexes to ensure that only one of its copies runs at any one time:

  • {Hash of Machine GUID}

Information Theft

This Ransomware gathers the following data:

  • Machine Name
  • IP

Other Details

This Ransomware connects to the following URL(s) to get the affected system's IP address:

  • http://bot.{BLOCKED}myipaddress.com

It connects to the following website to send and receive information:

  • {BLOCKED}.{BLOCKED}.{BLOCKED}8.168
  • {BLOCKED}.{BLOCKED}.211.81

It does the following:

  • After encrypting files it will executed commands to display its ransom note:
    • "%Program Files%\Internet Explorer\iexplore.exe" -k "%Application Data%\Adobe\Acrobat\9.0\YOUR_FILES_ARE_ENCRYPTED.HTML"
  • It encrypts files which can be found in the following locations:
    • Removable Drives
    • Fixed Drives
    • Shared Drives
    • Network Drives

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, and 8.)

Ransomware Routine

This Ransomware encrypts files with the following extensions:

  • .docx
  • .docm
  • .xlsm
  • .xlsb
  • .xlsx
  • .pptm
  • .pptx
  • .epub
  • .jpeg
  • .accdb
  • .conf
  • .config
  • .azw1
  • .azw3
  • .azw4
  • .apnx
  • .mobi
  • .html
  • .class
  • .java
  • .aspx
  • .sqllite
  • .indd
  • .number
  • .pages
  • .crwl
  • .tiff
  • .jfif
  • .pspimage
  • .mpeg
  • .movie
  • .mp4v
  • .mpv2
  • .aepx
  • .camproj
  • .dash
  • .gzip
  • .vmdk
  • .toast
  • .disc

It avoids encrypting files with the following strings in their file path:

  • \Windows
  • \$Recycle.Bin
  • \Microsoft
  • \Mozilla Firefox
  • \Opera
  • \Internet Explorer
  • \Temp
  • \Local
  • \LocalLow
  • \Chrome

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

  • {encrypted file directory}\YOUR_FILES_ARE_ENCRYPTED.HTML

  SOLUTION

Minimum Scan Engine:

9.750

FIRST VSAPI PATTERN FILE:

14.156.06

FIRST VSAPI PATTERN DATE:

28 Mar 2018

VSAPI OPR PATTERN File:

14.157.00

VSAPI OPR PATTERN Date:

29 Mar 2018

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

Identify and terminate files detected as Ransom_CRYPCHIM.CE

[ Learn More ]
  1. Windows Task Manager may not display all running processes. In this case, please use a third-party process viewer, preferably Process Explorer, to terminate the malware/grayware/spyware file. You may download the said tool here.
  2. If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
  3. If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.

Step 4

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.  
  • YOUR_FILES_ARE_ENCRYPTED.HTML

Step 5

Scan your computer with your Trend Micro product to delete files detected as Ransom_CRYPCHIM.CE. 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 the following Trend Micro Support pages for more information:

Step 6

Restore encrypted files from backup.


Did this description help? Tell us how we did.