Analysis by: Mariefher Grace Villanueva
ALIASES:

Trojan.GenericKD.79743405 (BITDEFENDER)

 PLATFORM:

Windows

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

Infection Channel: Downloaded from the Internet, 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: 8,905,591 bytes
File Type: JS
Initial Samples Received Date: 24 Mar 2026
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 drops the following files:

  • %Public%\Orio.png → contains Base64-encoded payload data disguised as a PNG image
  • %Public%\Brio.png → contains encrypted payload data disguised as a PNG image
  • %User Temp%\{8 random characters or numbers}.{3 random characters or numbers}.ps1 → stub PowerShell script file
  • %User Temp%\{8 random characters or numbers}.{3 random characters or numbers}.psm1 → PowerShell module file
  • %AppDataLocal%\Microsoft\Windows\PowerShell\StartupProfileData-Interactive → PowerShell profile data for persistence

(Note: %Public% is the folder that serves as a repository of files or folders common to all users, which is usually C:\Users\Public in Windows Vista, 7, and 8.. %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).. %AppDataLocal% is the Local Application Data folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

It adds the following processes:

  • "%System%\wscript.exe" %User Temp%\{Malware Filename}.js
  • "%System%\WindowsPowerShell\v1.0\powershell.exe" -Noexit -nop -c iex([Text.Encoding]::Unicode.GetString([Convert]::FromBase64String({Base64 payload})))

(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(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

  SOLUTION

Minimum Scan Engine: 9.800
FIRST VSAPI PATTERN FILE: 20.842.04
FIRST VSAPI PATTERN DATE: 24 Mar 2026
VSAPI OPR PATTERN File: 20.843.00
VSAPI OPR PATTERN Date: 25 Mar 2026

Step 1

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 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.
  • %Public%\Orio.png → contains Base64-encoded payload data disguised as a PNG image
  • %Public%\Brio.png → contains encrypted payload data disguised as a PNG image
  • %User Temp%\{8 random characters or numbers}.{3 random characters or numbers}.ps1 → stub PowerShell script file
  • %User Temp%\{8 random characters or numbers}.{3 random characters or numbers}.psm1 → PowerShell module file
  • %AppDataLocal%\Microsoft\Windows\PowerShell\StartupProfileData-Interactive → PowerShell profile data for persistence

Step 4

Scan your computer with your Trend Micro product to delete files detected as Trojan.JS.RUNNER.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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