Analysis by: Alyssa Christelle Ramos
ALIASES:

Trojan-Ransom.Crysis, Trojan-Ransom.Crysis (IKARUS)

 PLATFORM:

Windows

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

Infection Channel: Downloaded from the Internet

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: 390,032 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 27 Apr 2021
Payload: Terminates processes

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:

  • {Malware Path}\takeaway.ps1 → detected as Trojan.PS1.CRYSIS.AA → responsible for stopping AV services and executing the purgeMemory.ps1 and the ransomware sample
  • {Malware Path}\winhost.exe → detected as Ransom.Win32.CRYSIS.TIBGHR
  • {Malware Path}\purgeMemory.ps1 → detected as Trojan.PS1.KILLSVC.A
  • {Malware Path}\NS2.exe → detected as HackTool.Win32.NetTool.A

It adds the following processes:

  • "%System%\WindowsPowerShell\v1.0\powershell.exe" -ExecutionPolicy Bypass -noLogo -noProfile -File takeaway.ps1 winhost
  • "{Malware Path}\winhost.exe"
  • "%System%\WindowsPowerShell\v1.0\powershell.exe" -ExecutionPolicy Bypass -noLogo -noProfile -File purgeMemory.ps1

(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

Process Termination

This Trojan terminates the following services if found on the affected system:

  • Dell PBA
  • Warsaw Technology
  • OfficeScan
  • Huorong
  • QQPCMgr
  • Client Agent
  • SentinelOne
  • Cybereason
  • Kingsoft Core
  • eScan
  • Acronis Ransomware
  • Huorong
  • QQPCMgr
  • CompLogic
  • Sybereason
  • VIPRE
  • Naver
  • AhnLab
  • G DATA
  • N-able
  • F-Secure
  • K7Real
  • Endpoint
  • Safedog
  • Trend Micro
  • Avira
  • MBAB
  • Microsoft Anti
  • estsoft
  • netflow
  • Bitdefender
  • Norton
  • Kaspersky
  • ESET
  • Panda
  • 360
  • AVG
  • webroot
  • Avast
  • Symantec
  • protection
  • antimalware
  • Windows Defender
  • McAfee
  • V3
  • Traps
  • Panda
  • Sophos

Other Details

This Trojan does the following:

  • It displays console that logs all its activities and does the following:
    • displays green if winhost.exe is running; else, displays red
    • displays "CPU" + random numbers if winhost.exe is running; else, displays "NO PROCESS RUNNING? :-("

  SOLUTION

Minimum Scan Engine: 9.800
FIRST VSAPI PATTERN FILE: 16.698.05
FIRST VSAPI PATTERN DATE: 05 May 2021
VSAPI OPR PATTERN File: 16.699.00
VSAPI OPR PATTERN Date: 05 May 2021

Step 1

Trend Micro Predictive Machine Learning detects and blocks malware at the first sign of its existence, before it executes on your system. When enabled, your Trend Micro product detects this malware under the following machine learning name:

     
    • Troj.Win32.TRX.XXPE50FSX009

Step 2

Before doing any scans, Windows 7, Windows 8, Windows 8.1, and Windows 10 users must disable System Restore to allow full scanning of their computers.

Step 3

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 4

Search and delete these files

[ Learn More ]
There may be some component 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}\takeaway.ps1
  • {Malware Path}\winhost.exe
  • {Malware Path}\purgeMemory.ps1
  • {Malware Path}\NS2.exe

Step 5

Scan your computer with your Trend Micro product to delete files detected as Trojan.Win32.CRYSIS.C. 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:


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