Analysis by: Marcus Ma. Antonio Capistrano
ALIASES:

Ransom:Win32/InsaneCrypt (Microsoft), Ransom.DeusCrypt.S1821434 (QUICKHEAL)

 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 is capable of encrypting files in the affected system.

It drops files as ransom note.

  TECHNICAL DETAILS

File Size: 265,728 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 21 Jan 2018
Payload: Displays windows, 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.

Other Details

This Ransomware does the following:

  • It deletes shadow copies using the following commands:
    • /C vssadmin Delete Shadows /All /Quiet
    • /C wmic shadowcopy delete
  • It disables or turns off Windows Error Recovery Screen on Startup using the following command:
    • bcdedit / set{ default } bootstatuspolicy ignoreallfailures
  • It disables Startup Repair from running using the following command:
    • bcdedit / set{ default } recoveryenabled no
  • It deletes the backup catalog using the following command:
    • wbadmin delete catalog - quiet

It is capable of encrypting files in the affected system.

Ransomware Routine

This Ransomware avoids encrypting files found in the following folders:

  • Default
  • All Users
  • Content.IE5
  • Temporary Internet Files
  • AppData
  • Windows
  • Microsoft
  • Intel
  • $Recycle.Bin

It appends the following extension to the file name of the encrypted files:

  • .[insane@{BLOCKED}l.cc].insane

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

  • {Encrypted file directory}\How_decrypt_files.txt

It leaves text files that serve as ransom notes containing the following text:

  • Hello!
    If you want restore your files write on email - insane@{BLOCKED}l.cc

NOTES:

When this ransomware is executed, it displays a console window which shows the encryption process.

After the ransomware has finished encrypting, the console window exits.

  SOLUTION

Minimum Scan Engine: 9.850
FIRST VSAPI PATTERN FILE: 13.920.02
FIRST VSAPI PATTERN DATE: 22 Jan 2018
VSAPI OPR PATTERN File: 13.921.00
VSAPI OPR PATTERN Date: 23 Jan 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

Search and delete these files

[ 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.
  • {Encrypted file directory}\How_decrypt_files.txt

Step 4

Scan your computer with your Trend Micro product to delete files detected as RANSOM_INSANECRYPT.THABBH. 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 5

Restore encrypted files from backup.

NOTES:

Enable services disabled using the command prompt.

Run cmd.exe as administrator.

To enable Windows Error Recovery Screen on Startup, use the following command:

bcdedit /set {default} bootstatuspolicy displayallfailures

To enable Startup Repair, use the following command:

/bcedit /set {default} recoveryenabled Yes


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