Malware Analysis Report

2025-08-05 20:46

Sample ID 240302-2ahefahh81
Target Chernobyl.exe
SHA256 2b6266f14d2ed46e921168fd2b4a5510f40c69cd591800d17ae8ca31fcde28c6
Tags
evasion persistence trojan
score
10/10

Table of Contents

Analysis Overview

MITRE ATT&CK

Enterprise Matrix V15

Analysis: static1

Detonation Overview

Signatures

Analysis: behavioral1

Detonation Overview

Command Line

Signatures

Processes

Network

Files

Analysis Overview

score
10/10

SHA256

2b6266f14d2ed46e921168fd2b4a5510f40c69cd591800d17ae8ca31fcde28c6

Threat Level: Known bad

The file Chernobyl.exe was found to be: Known bad.

Malicious Activity Summary

evasion persistence trojan

UAC bypass

Modifies WinLogon for persistence

Disables RegEdit via registry modification

Disables Task Manager via registry modification

Modifies WinLogon

Checks whether UAC is enabled

Drops file in System32 directory

Drops file in Windows directory

Unsigned PE

Enumerates physical storage devices

System policy modification

Modifies registry class

Suspicious use of WriteProcessMemory

MITRE ATT&CK

Analysis: static1

Detonation Overview

Reported

2024-03-02 22:22

Signatures

Unsigned PE

Description Indicator Process Target
N/A N/A N/A N/A

Analysis: behavioral1

Detonation Overview

Submitted

2024-03-02 22:22

Reported

2024-03-02 22:53

Platform

win11-20240221-en

Max time kernel

1484s

Max time network

1498s

Command Line

"C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe"

Signatures

Modifies WinLogon for persistence

persistence
Description Indicator Process Target
Set value (str) \REGISTRY\MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell = "explorer.exe, cluttscape.exe" C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe N/A

UAC bypass

evasion trojan
Description Indicator Process Target
Set value (int) \REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\EnableLUA = "0" C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe N/A

Disables RegEdit via registry modification

evasion
Description Indicator Process Target
Set value (int) \REGISTRY\USER\S-1-5-21-160263616-143223877-1356318919-1000\Software\Microsoft\Windows\CurrentVersion\Policies\System\DisableRegistryTools = "1" C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe N/A

Disables Task Manager via registry modification

evasion

Checks whether UAC is enabled

evasion trojan
Description Indicator Process Target
Key value queried \REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\EnableLUA C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe N/A
Set value (int) \REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\EnableLUA = "0" C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe N/A

Modifies WinLogon

persistence
Description Indicator Process Target
Set value (int) \REGISTRY\MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows NT\CurrentVersion\Winlogon\AutoRestartShell = "0" C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe N/A
Set value (int) \REGISTRY\MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows NT\CurrentVersion\Winlogon\DisableCAD = "1" C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe N/A

Drops file in System32 directory

Description Indicator Process Target
File opened for modification C:\Windows\SysWOW64\kill.ico C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe N/A

Drops file in Windows directory

Description Indicator Process Target
File opened for modification C:\Windows\cluttscape.exe C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe N/A
File created C:\Windows\cluttscape.exe C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe N/A

Enumerates physical storage devices

Modifies registry class

Description Indicator Process Target
Set value (str) \REGISTRY\MACHINE\SOFTWARE\Classes\Unknown\DefaultIcon\ = "C:\\Windows\\SysWow64\\kill.ico" C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe N/A

Suspicious use of WriteProcessMemory

Description Indicator Process Target
PID 3904 wrote to memory of 960 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 960 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 960 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 420 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 420 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 420 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 960 wrote to memory of 4460 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 960 wrote to memory of 4460 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 960 wrote to memory of 4460 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 3904 wrote to memory of 252 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 252 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 252 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 4052 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 4052 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 4052 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 648 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 648 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 648 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 4644 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 4644 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 4644 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 420 wrote to memory of 3984 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 420 wrote to memory of 3984 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 420 wrote to memory of 3984 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 3904 wrote to memory of 4336 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 4336 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 4336 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 3588 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 3588 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 3588 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 4052 wrote to memory of 4488 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 4052 wrote to memory of 4488 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 4052 wrote to memory of 4488 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 252 wrote to memory of 248 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 252 wrote to memory of 248 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 252 wrote to memory of 248 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 3904 wrote to memory of 1244 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 1244 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 1244 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 4936 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 4936 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 4936 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 648 wrote to memory of 2600 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 648 wrote to memory of 2600 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 648 wrote to memory of 2600 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 3904 wrote to memory of 3744 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 3744 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 3744 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 1256 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 1256 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 3904 wrote to memory of 1256 N/A C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe C:\Windows\SysWOW64\cmd.exe
PID 4644 wrote to memory of 2664 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 4644 wrote to memory of 2664 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 4644 wrote to memory of 2664 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 4336 wrote to memory of 4840 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 4336 wrote to memory of 4840 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 4336 wrote to memory of 4840 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 3588 wrote to memory of 3672 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 3588 wrote to memory of 3672 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 3588 wrote to memory of 3672 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 1244 wrote to memory of 4356 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 1244 wrote to memory of 4356 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 1244 wrote to memory of 4356 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe
PID 1256 wrote to memory of 1872 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\rundll32.exe

System policy modification

evasion
Description Indicator Process Target
Set value (int) \REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\shutdownwithoutlogon = "0" C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe N/A
Set value (int) \REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer\UseDefaultTile = "1" C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe N/A
Set value (int) \REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\EnableLUA = "0" C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe N/A

Processes

C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe

"C:\Users\Admin\AppData\Local\Temp\Chernobyl.exe"

C:\Windows\SysWOW64\cmd.exe

"C:\Windows\System32\cmd.exe" /k start RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters && exit

C:\Windows\SysWOW64\cmd.exe

"C:\Windows\System32\cmd.exe" /k start RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters && exit

C:\Windows\SysWOW64\rundll32.exe

RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters

C:\Windows\SysWOW64\cmd.exe

"C:\Windows\System32\cmd.exe" /k start RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters && exit

C:\Windows\SysWOW64\cmd.exe

"C:\Windows\System32\cmd.exe" /k start RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters && exit

C:\Windows\SysWOW64\cmd.exe

"C:\Windows\System32\cmd.exe" /k start RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters && exit

C:\Windows\SysWOW64\cmd.exe

"C:\Windows\System32\cmd.exe" /k start RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters && exit

C:\Windows\SysWOW64\rundll32.exe

RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters

C:\Windows\SysWOW64\cmd.exe

"C:\Windows\System32\cmd.exe" /k start RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters && exit

C:\Windows\SysWOW64\cmd.exe

"C:\Windows\System32\cmd.exe" /k start RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters && exit

C:\Windows\SysWOW64\rundll32.exe

RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters

C:\Windows\SysWOW64\rundll32.exe

RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters

C:\Windows\SysWOW64\cmd.exe

"C:\Windows\System32\cmd.exe" /k start RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters && exit

C:\Windows\SysWOW64\cmd.exe

"C:\Windows\System32\cmd.exe" /k start RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters && exit

C:\Windows\SysWOW64\rundll32.exe

RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters

C:\Windows\SysWOW64\cmd.exe

"C:\Windows\System32\cmd.exe" /k start RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters && exit

C:\Windows\SysWOW64\cmd.exe

"C:\Windows\System32\cmd.exe" /k start RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters && exit

C:\Windows\SysWOW64\rundll32.exe

RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters

C:\Windows\SysWOW64\rundll32.exe

RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters

C:\Windows\SysWOW64\rundll32.exe

RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters

C:\Windows\SysWOW64\rundll32.exe

RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters

C:\Windows\SysWOW64\rundll32.exe

RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters

C:\Windows\SysWOW64\rundll32.exe

RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters

C:\Windows\SysWOW64\rundll32.exe

RUNDLL32.EXE user32.dll,UpdatePerUserSystemParameters

Network

Country Destination Domain Proto
US 8.8.8.8:53 55.36.223.20.in-addr.arpa udp
US 204.79.197.200:443 tse1.mm.bing.net tcp
US 204.79.197.200:443 tse1.mm.bing.net tcp
US 204.79.197.200:443 tse1.mm.bing.net tcp
US 204.79.197.200:443 tse1.mm.bing.net tcp
US 204.79.197.200:443 tse1.mm.bing.net tcp

Files

memory/3904-0-0x0000000074D10000-0x00000000754C1000-memory.dmp

memory/3904-1-0x0000000000420000-0x000000000047C000-memory.dmp

memory/3904-2-0x0000000004EB0000-0x0000000004F42000-memory.dmp

memory/3904-3-0x0000000005500000-0x0000000005AA6000-memory.dmp

memory/3904-4-0x0000000004E80000-0x0000000004E90000-memory.dmp

C:\Users\Admin\Desktop\äœ∞ÿ♪¶3∩é™▲±╤▼╩╠◙π¾∞œ♦▐×╩čεšπ¤4█µŸ▬±¼æÇæ±ß♀é¶Â▬∞—ÿ╩◘↑♥¼♦¢♥▀æÿ♦♪ń3š¾Σ☺∞√▲ž√■₧☺£Æ¬♥▐ě¤éä╥¬—φæ↑▌▐5öÇ╤õø

MD5 9e1e5883c74742a497cf5c272ccd2321
SHA1 2cf33e34d08b8e17743a60352baffef4b6f02dee
SHA256 ca687b6a7c3d29b566f3e1988b9f877b51d9a83ee25ffe0755a8dcd3eb5f434a
SHA512 f2284f0c624cc07a65c16f87865bb98aaa176b1d8b45cd4fbcc1143c9c2297fe6b1d4db55ef054be2bc151c8cc25ff4da7c997b7d38dae3dccd2ffe1c3c01a6b

memory/3904-309-0x00000000061C0000-0x00000000061CA000-memory.dmp

memory/3904-310-0x0000000074D10000-0x00000000754C1000-memory.dmp

memory/3904-311-0x0000000004E80000-0x0000000004E90000-memory.dmp