asyncrat | 3fb3f31a4d3a167fb2e824fa3c45c40f4f3aa77b0bd8231b054bd4ace7ed2b86

Analysis

max time kernel
148s
max time network
153s
platform
windows11-ltsc_2024_x64
resource
win11ltsc2024-20260709-en
resource tags

arch:x64arch:x86image:win11ltsc2024-20260709-enlocale:en-usos:windows11-ltsc_2024-x64systemwindows
submitted
26/08/2026, 16:07

Sharing

Copy URL Twitter E-mail

Report Analysis Logs

General

Target
nanocore.exe
Size 45KB
Sample260826-tk35wssblf
SHA256 3fb3f31a4d3a167fb2e824fa3c45c40f4f3aa77b0bd8231b054bd4ace7ed2b86
MD5 5aab96ac6773fde94f4027228de98147
SHA1 5f6c941cd9da4f188169c0210415f98bb0ea17af
SHA512 f4de09963e9c271a1d2f9670344869ccc73713b9ada7ad0289f6a322a950d080e1c8ac5cfdca7b7a6b3c4a2d5d7f18535967d68dd616df9ede09e8b79a3e260c
SSDEEP 768:BuASNTR4ydbWUnrGJmo2q7qpW+VgO8tPIozjbKgX3idDJnkEOJ4xWlHBDZjx:BuASNTRZ22VRFo3bdXSdiEOcihdjx
TLSH
T1BC231A003BE9827AF2BE4F789CF26105467AF6632603D94D2CC451DB5623BC6C6426FE
MD5 SHA1 SHA512 SSDEEP TLSH

Score

10^/10

refuel-casino.co command_and_control defense_evasion discovery execution asyncrat persistence rat

Malware Config

Extracted

Family

asyncrat

Version

0.5.8

Botnet

refuel-casino.co

refuel-casino.co:80
refuel-casino.co:8080
refuel-casino.co:443
refuel-casino.co:8443
refuel-casino.co:6606
refuel-casino.co:22

Mutex

0ue8qloTv0yj

Attributes

delay
3
install
true
install_file
GoogleUpdate.exe
install_folder
%AppData%

aes.plain

Signatures

Family: AsyncRat
AsyncRAT is designed to remotely monitor and control other computers written in C#.
rat asyncrat

Async RAT payload 1 IoCs

rat

resource	yara_rule
behavioral2/files/0x000d00000001c504-10.dat	family_asyncrat

Executes dropped EXE 2 IoCs

pid	Process
4168	GoogleUpdate.exe
1092	GoogleUpdate.exe

Outbound SSH connection to public host 2 TTPs 4 IoCs

SSH is used for remote access. This may indicate SSH host discovery, encrypted C2 traffic, or data exfiltration.

command_and_control

Protocol Tunneling

T1572

Network Service Discovery

T1046

description	flow	ioc	pid	Process
SSH destination	3	172.67.141.27:22		Process not Found
SSH destination	6	104.21.54.187:22		Process not Found
SSH destination	7	172.67.141.27:22		Process not Found
SSH destination	2	104.21.54.187:22	4168	GoogleUpdate.exe

Enumerates physical storage devices 1 TTPs
Attempts to interact with connected storage/optical drive(s).

System Information Discovery
T1082

Executes a command shell one-liner 1 TTPs 2 IoCs

Execution of a cmd.exe one-liner (/c "close" or /k "keep") is a common script/loader stage.

execution

Windows Command Shell

T1059.003

pid	Process
4672	cmd.exe
3604	cmd.exe

System Location Discovery: System Language Discovery 1 TTPs 7 IoCs

Attempt gather information about the system language of a victim in order to infer the geographical location of that host.

discovery

System Language Discovery

T1614.001

description	ioc	Process
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	schtasks.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	timeout.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	GoogleUpdate.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	GoogleUpdate.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	nanocore.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	cmd.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	cmd.exe

Delays execution with timeout.exe 1 IoCs

defense_evasion

pid	Process
1280	timeout.exe

Scheduled Task/Job: Scheduled Task 1 TTPs 1 IoCs

Schtasks is often used by malware for persistence or to perform post-infection execution.

persistence execution

Scheduled Task

T1053.005

pid	Process
5176	schtasks.exe

Suspicious behavior: EnumeratesProcesses 31 IoCs

pid	Process
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe
3752	nanocore.exe

Suspicious use of AdjustPrivilegeToken 2 IoCs

description	pid	Process
Token: SeDebugPrivilege	3752	nanocore.exe
Token: SeDebugPrivilege	4168	GoogleUpdate.exe

Suspicious use of WriteProcessMemory 5 IoCs

description	pid	Process	procid_target
PID 3752 wrote to memory of 3604	3752	nanocore.exe	89
PID 3752 wrote to memory of 4672	3752	nanocore.exe	91
PID 3604 wrote to memory of 5176	3604	cmd.exe	93
PID 4672 wrote to memory of 1280	4672	cmd.exe	94
PID 4672 wrote to memory of 1092	4672	cmd.exe	97

C:\Users\Admin\AppData\Local\Temp\nanocore.exe
"C:\Users\Admin\AppData\Local\Temp\nanocore.exe"
1⤵
- System Location Discovery: System Language Discovery
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:3752
- C:\Windows\SysWOW64\cmd.exe
  "C:\Windows\System32\cmd.exe" /c schtasks /create /f /sc onlogon /rl highest /tn "GoogleUpdate" /tr '"C:\Users\Admin\AppData\Roaming\GoogleUpdate.exe"' & exit
  2⤵
  - Executes a command shell one-liner
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:3604
- - C:\Windows\SysWOW64\schtasks.exe
    schtasks /create /f /sc onlogon /rl highest /tn "GoogleUpdate" /tr '"C:\Users\Admin\AppData\Roaming\GoogleUpdate.exe"'
    3⤵
    - System Location Discovery: System Language Discovery
    - Scheduled Task/Job: Scheduled Task
    PID:5176
- C:\Windows\SysWOW64\cmd.exe
  C:\Windows\system32\cmd.exe /c ""C:\Users\Admin\AppData\Local\Temp\tmp5A2C.tmp.bat""
  2⤵
  - Executes a command shell one-liner
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:4672
- - C:\Windows\SysWOW64\timeout.exe
    timeout 3
    3⤵
    - System Location Discovery: System Language Discovery
    - Delays execution with timeout.exe
    PID:1280
- - C:\Users\Admin\AppData\Roaming\GoogleUpdate.exe
    "C:\Users\Admin\AppData\Roaming\GoogleUpdate.exe"
    3⤵
    - Executes dropped EXE
    - System Location Discovery: System Language Discovery
    PID:1092

C:\Users\Admin\AppData\Roaming\GoogleUpdate.exe
"C:\Users\Admin\AppData\Roaming\GoogleUpdate.exe"
1⤵
- Executes dropped EXE
- Outbound SSH connection to public host
- System Location Discovery: System Language Discovery
- Suspicious use of AdjustPrivilegeToken
PID:4168

Network

MITRE ATT&CK Enterprise v16

Reconnaissance

Resource Development

Initial Access

Execution

Command and Scripting Interpreter

T1059

Windows Command Shell

T1059.003

Scheduled Task/Job

T1053

Scheduled Task

T1053.005

Persistence

Scheduled Task/Job

T1053

Scheduled Task

T1053.005

Privilege Escalation

Scheduled Task/Job

T1053

Scheduled Task

T1053.005

Defense Evasion

Credential Access

Discovery

Network Service Discovery

T1046

System Information Discovery

T1082

System Location Discovery

T1614

System Language Discovery

T1614.001

Lateral Movement

Collection

Command and Control

Protocol Tunneling

T1572

Exfiltration

Impact

Replay Monitor

Loading Replay Monitor...

Downloads

tmp5A2C.tmp.bat

Path C:\Users\Admin\AppData\Local\Temp\tmp5A2C.tmp.bat
Size 156B
SHA256 039bf7c12463597f7cf3096b095358a0412d91ebd1dbbd26b6f5b623bba75d2b
MD5 94dee5ae381607ace06d56753ba0ea37
SHA1 a725174446aea532b3a246dc420e052fbc8af8c0
SHA512 d4cc7d1cf81219ae7df5e19bde5cfea228647a18f1a17a6b5d6d7369357da458504864484a90d26776b8662354d2330ebd86061274544d0ec84be772e595f427
TLSH
T167C02B5361C9EA7F2805A81713FFD9CD91B26C5A3F44FB00C704841E22C0888F4ED382
MD5 SHA1 SHA512 TLSH

Submit Download

GoogleUpdate.exe

Path C:\Users\Admin\AppData\Roaming\GoogleUpdate.exe
Size 45KB
SHA256 3fb3f31a4d3a167fb2e824fa3c45c40f4f3aa77b0bd8231b054bd4ace7ed2b86
MD5 5aab96ac6773fde94f4027228de98147
SHA1 5f6c941cd9da4f188169c0210415f98bb0ea17af
SHA512 f4de09963e9c271a1d2f9670344869ccc73713b9ada7ad0289f6a322a950d080e1c8ac5cfdca7b7a6b3c4a2d5d7f18535967d68dd616df9ede09e8b79a3e260c
SSDEEP 768:BuASNTR4ydbWUnrGJmo2q7qpW+VgO8tPIozjbKgX3idDJnkEOJ4xWlHBDZjx:BuASNTRZ22VRFo3bdXSdiEOcihdjx
TLSH
T1BC231A003BE9827AF2BE4F789CF26105467AF6632603D94D2CC451DB5623BC6C6426FE
MD5 SHA1 SHA512 SSDEEP TLSH

Submit Download

memory/3752-0-0x0000000075162000-0x0000000075163000-memory.dmp

Download

memory/3752-1-0x0000000000C40000-0x0000000000C52000-memory.dmp

Download

memory/3752-2-0x0000000075150000-0x000000007590C000-memory.dmp

Download

memory/3752-3-0x0000000005740000-0x00000000057DC000-memory.dmp

Download

memory/3752-9-0x0000000075150000-0x000000007590C000-memory.dmp

Download

memory/4168-12-0x0000000075150000-0x000000007590C000-memory.dmp

Download

memory/4168-14-0x0000000075150000-0x000000007590C000-memory.dmp

Download