Analysis by: Kyra-Melody Gonzales
ALIASES:

Trojan:Win32/LummaStealer.SX!MTB (MICROSOFT), Gen:Variant.Zusy.589746 (BITDEFENDER), Trojan.Win32.Krypt (IKARUS)

 PLATFORM:

Windows

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

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.

It executes then deletes itself afterward.

It hides files, processes, and/or registry entries.

  TECHNICAL DETAILS

File Size: 14,101,504 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 10 Oct 2025

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 a copy of itself in the following folders using different file names:

  • %User Profile%\aoc.bat

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name} on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

It adds the following processes:

  • "%System%\cmd.exe" /C mkdir %System%\{8 random lowercase letters}\;
  • "%System%\cmd.exe" /C move /Y "%User Temp%\{another 8 random lowercase letters}.exe" %System%\{8 random lowercase letters}\;
  • "%System%\sc.exe" create {8 random lowercase letters} binPath= "%System%\{8 random lowercase letters}\{another 8 random lowercase letters}.exe /d\"{malware file path and name}\"" type= own start= auto DisplayName= "wifi support";
  • "%System%\sc.exe" description {8 random lowercase letters} "wifi internet conection";
  • "%System%\sc.exe" start {8 random lowercase letters};
  • "%System%\netsh.exe" advfirewall firewall add rule name="Host-process for services of Windows" dir=in action=allow program="%System%\svchost.exe" enable=yes>nul;

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

It creates the following folders:

  • %System%\{8 random lowercase letters}\

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

It executes then deletes itself afterward.

Autostart Technique

This Trojan registers itself as a system service to ensure its automatic execution at every system startup by adding the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\{8 random lowercase letters}
ImagePath = %System%\{8 random lowercase letters}\{another 8 random lowercase letters}.exe /d"{malware file path and name}

Other System Modifications

This Trojan modifies the following file(s):

  • %User Profile%\aoc.bat

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name} on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\{8 random lowercase letters}
DisplayName = "wifi support"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\{8 random lowercase letters}
Start = "SERVICE_AUTO_START"

Rootkit Capabilities

This Trojan hides files, processes, and/or registry entries.

Dropping Routine

This Trojan drops the following files:

  • %User Temp%\{another 8 random lowercase letters}.exe
  • %System%\{8 random lowercase letters}\{another 8 random lowercase letters}.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(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).. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

Other Details

This Trojan connects to the following possibly malicious URL:

  • {BLOCKED}.{BLOCKED}.75.39
  • {BLOCKED}.{BLOCKED}.98.2
  • {BLOCKED}.{BLOCKED}.152.6
  • {BLOCKED}.{BLOCKED}.98.3
  • {BLOCKED}.{BLOCKED}.158.30
  • {BLOCKED}.{BLOCKED}.84.42
  • {BLOCKED}.{BLOCKED}.158.32
  • {BLOCKED}.{BLOCKED}.33.10
  • {BLOCKED}.{BLOCKED}.179.210
  • {BLOCKED}.{BLOCKED}.172.98
  • {BLOCKED}.{BLOCKED}.94.84
  • {BLOCKED}.{BLOCKED}.152.3
  • {BLOCKED}.{BLOCKED}.131.174
  • {BLOCKED}.{BLOCKED}.0.133
  • {BLOCKED}.{BLOCKED}.120.207
  • {BLOCKED}.{BLOCKED}.6.212
  • {BLOCKED}.{BLOCKED}.190.29
  • {BLOCKED}.{BLOCKED}.129.198
  • {BLOCKED}.{BLOCKED}.220.163
  • {BLOCKED}.{BLOCKED}.220.132
  • {BLOCKED}.{BLOCKED}.152.35
  • {BLOCKED}.{BLOCKED}.60.135
  • {BLOCKED}.{BLOCKED}.208.34
  • {BLOCKED}.{BLOCKED}.167.99
  • {BLOCKED}.{BLOCKED}.250.83
  • {BLOCKED}.{BLOCKED}.65.133
  • {BLOCKED}.{BLOCKED}.149.210
  • {BLOCKED}.{BLOCKED}.91.34
  • {BLOCKED}.{BLOCKED}.43.206
  • {BLOCKED}.{BLOCKED}.72.117
  • {BLOCKED}.{BLOCKED}.2.216
  • {BLOCKED}.{BLOCKED}.183.179
  • {BLOCKED}.{BLOCKED}.29.99
  • {BLOCKED}.{BLOCKED}.105.46
  • {BLOCKED}.{BLOCKED}.73.4
  • {BLOCKED}.{BLOCKED}.4.138
  • {BLOCKED}.{BLOCKED}.130.58
  • {BLOCKED}.{BLOCKED}.156.195
  • {BLOCKED}.{BLOCKED}.15.19
  • {BLOCKED}.{BLOCKED}.14.107
  • {BLOCKED}.{BLOCKED}.220.170
  • {BLOCKED}.{BLOCKED}.24.202
  • {BLOCKED}.{BLOCKED}.192.7
  • {BLOCKED}.{BLOCKED}.6.21
  • {BLOCKED}.{BLOCKED}.143.56
  • {BLOCKED}.{BLOCKED}.5.13
  • {BLOCKED}.{BLOCKED}.101.33
  • {BLOCKED}.{BLOCKED}.215.43
  • {BLOCKED}.{BLOCKED}.165.147
  • {BLOCKED}.{BLOCKED}.63.107
  • {BLOCKED}.{BLOCKED}.17.186
  • {BLOCKED}.{BLOCKED}.150.18
  • {BLOCKED}.{BLOCKED}.48.149
  • {BLOCKED}.{BLOCKED}.167.109
  • {BLOCKED}.{BLOCKED}.73.196
  • {BLOCKED}.{BLOCKED}.172.36
  • {BLOCKED}.{BLOCKED}.251.72
  • {BLOCKED}.{BLOCKED}.48.2
  • {BLOCKED}.{BLOCKED}.236.193
  • {BLOCKED}.{BLOCKED}.195.34
  • {BLOCKED}.{BLOCKED}.37.162
  • {BLOCKED}.{BLOCKED}.87.9
  • {BLOCKED}.{BLOCKED}.144.76
  • {BLOCKED}.{BLOCKED}.32.19
  • {BLOCKED}.{BLOCKED}.13.209
  • {BLOCKED}.{BLOCKED}.78.99
  • {BLOCKED}.{BLOCKED}.14.33
  • {BLOCKED}.{BLOCKED}.245.79
  • {BLOCKED}.{BLOCKED}.221.35
  • {BLOCKED}.{BLOCKED}.99.71
  • {BLOCKED}.{BLOCKED}.7.75
  • {BLOCKED}.{BLOCKED}.29.119
  • {BLOCKED}.{BLOCKED}.24.9
  • {BLOCKED}.{BLOCKED}.166.109
  • {BLOCKED}.{BLOCKED}.248.20
  • {BLOCKED}.{BLOCKED}.17.172
  • {BLOCKED}.{BLOCKED}.202.3
  • {BLOCKED}.{BLOCKED}.17.178
  • {BLOCKED}.{BLOCKED}.128.57
  • {BLOCKED}.{BLOCKED}.17.170
  • {BLOCKED}.{BLOCKED}.183.26
  • {BLOCKED}.{BLOCKED}.64.236
  • {BLOCKED}.{BLOCKED}.242.123
  • {BLOCKED}.{BLOCKED}.142.84
  • {BLOCKED}.{BLOCKED}.154.7
  • {BLOCKED}.{BLOCKED}.31.18
  • {BLOCKED}.{BLOCKED}.6.22
  • {BLOCKED}.{BLOCKED}.241.162
  • {BLOCKED}.{BLOCKED}.228.130
  • {BLOCKED}.{BLOCKED}.191.136
  • {BLOCKED}.{BLOCKED}.5.229
  • {BLOCKED}.{BLOCKED}.14.19
  • {BLOCKED}.{BLOCKED}.220.138
  • {BLOCKED}.{BLOCKED}.130.23

It does the following:

  • Uses powershell to execute the obfuscated batch script to modify %User Profile%\aoc.bat

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name} 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: 20.560.04
FIRST VSAPI PATTERN DATE: 03 Nov 2025
VSAPI OPR PATTERN File: 20.561.00
VSAPI OPR PATTERN Date: 04 Nov 2025

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.XXPE50FFF098

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

Restart in Safe Mode, and then delete this registry key

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\{8 random lowercase letters}
    • ImagePath = %System%\{8 random lowercase letters}\{another 8 random lowercase letters}.exe /d"{malware file path and name}

Step 5

Delete this registry value

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\{8 random lowercase letters}
    • DisplayName = "wifi support"
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\{8 random lowercase letters}
    • Start = "SERVICE_AUTO_START"

Step 6

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.
  • %User Temp%\{another 8 random lowercase letters}.exe
  • %System%\{8 random lowercase letters}\{another 8 random lowercase letters}.exe

Step 7

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.
  • %System%\{8 random lowercase letters}\

Step 8

Restart in normal mode and scan your computer with your Trend Micro product for files detected as Trojan.Win32.TOFSEE.KM. 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 this Knowledge Base page for more information.

Step 9

Scan your computer with your Trend Micro product to delete files detected as Trojan.Win32.TOFSEE.KM. 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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