Analysis by: Wilbert Vidal
ALIASES:

Trojan.Win32.KillDisk.fz (Kaspersky); Win32.Trojan.Killdisk.Swud (Tencent)

 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: 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.

  TECHNICAL DETAILS

File Size: 626,520 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 26 May 2018
Payload: Drops files

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 adds the following folders:

  • %User Temp%/ns{5 random characters}.tmp ← Deleted Afterwards

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on 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.)

It drops the following files:

  • %User Temp%/ns{5 random characters}.tmp/System.dll ← Deleted Afterwards

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on 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 Trojan does the following:

  • Wipes Master Boot Record Data
    • It overwrites the portion of the physical drives with null values
  • Performs Shutdown

  SOLUTION

Minimum Scan Engine: 9.850
VSAPI OPR PATTERN File: 14.279.16
VSAPI OPR PATTERN Date: 27 May 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 this folder

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
  • %User Temp%/ns{5 random characters}.tmp

Step 4

Scan your computer with your Trend Micro product to delete files detected as TROJ_KILLDISK.IUE. 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:

NOTES:

Restore the system from backup or reinstall the operating system (OS).

Depending on the extent of the damage, and if the wiping of the MBR is unsuccessful, the system can be made bootable by doing a system repair using a Windows installer disk. If the Windows installer can still make the system boot up, recovery of the files will be futile as portions of the files were already corrupted.


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