Analysis
- user interaction
yes - max time kernel
149s - max time network
144s - platform
windows11-ltsc_2024_x64 - resource
win11ltsc2024-20260709-en - resource tags
- submitted
09/08/2026, 15:56
General
- Target MasonClient.exe
- Size 88KB
- Sample260809-tdbr3atybw
- SHA256 ab25277c78a76a3b54217c9363ee571a67c1ed4f049825ec32a0afa16d67edbc
Malware Config
Extracted
-
neptunerat
-
92.99.93.184:6868
-
filename
USB.exe
-
group
MasonGroup
-
key
lwijufbF8osb3Qex
-
rat_name
MasonRAT
Signatures
- Family: DonutLoader
DonutLoader is a position-independent code that enables in-memory execution of VBScript, JScript, EXE, DLL files and dotNET assemblies.
- Family: NeptuneRAT, MasonRAT
NeptuneRAT aka MasonRAT is a trojan written in C#.
- Detects DonutLoader 1 IoCs
- Detects NeptuneRAT stealer 1 IoCs
- Executes dropped EXE 4 IoCs
- Adds Run key to start application 2 TTPs 1 IoCs
- Enumerates physical storage devices 1 TTPs
Attempts to interact with connected storage/optical drive(s).
- System Location Discovery: System Language Discovery 1 TTPs 1 IoCs
Attempt gather information about the system language of a victim in order to infer the geographical location of that host.
- Scheduled Task/Job: Scheduled Task 1 TTPs 1 IoCs
Schtasks is often used by malware for persistence or to perform post-infection execution.
- Suspicious use of AdjustPrivilegeToken 4 IoCs
- Suspicious use of WriteProcessMemory 2 IoCs
- Uses Task Scheduler COM API 1 TTPs
The Task Scheduler COM API can be used to schedule applications to run on boot or at set times.
Processes
-
C:\Users\Admin\AppData\Local\Temp\MasonClient.exe"C:\Users\Admin\AppData\Local\Temp\MasonClient.exe"1⤵
- Adds Run key to start application
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
-
C:\Windows\System32\schtasks.exe"C:\Windows\System32\schtasks.exe" /create /f /sc minute /mo 1 /tn "MasonClient" /tr "C:\Users\Admin\AppData\Roaming\MasonClient.exe"2⤵
- Scheduled Task/Job: Scheduled Task
-
-
C:\Users\Admin\AppData\Local\Temp\tmpC2F8.tmp.exe"C:\Users\Admin\AppData\Local\Temp\tmpC2F8.tmp.exe"2⤵
- Executes dropped EXE
- System Location Discovery: System Language Discovery
-
-
C:\Users\Admin\AppData\Roaming\MasonClient.exeC:\Users\Admin\AppData\Roaming\MasonClient.exe1⤵
- Executes dropped EXE
- Suspicious use of AdjustPrivilegeToken
-
C:\Users\Admin\AppData\Roaming\MasonClient.exe"C:\Users\Admin\AppData\Roaming\MasonClient.exe"1⤵
- Executes dropped EXE
- Suspicious use of AdjustPrivilegeToken
-
C:\Users\Admin\AppData\Roaming\MasonClient.exe"C:\Users\Admin\AppData\Roaming\MasonClient.exe"1⤵
- Executes dropped EXE
- Suspicious use of AdjustPrivilegeToken
Network
MITRE ATT&CK Enterprise v16
Persistence
Boot or Logon Autostart Execution
1Registry Run Keys / Startup Folder
1Scheduled Task/Job
1Scheduled Task
1Privilege Escalation
Boot or Logon Autostart Execution
1Registry Run Keys / Startup Folder
1Scheduled Task/Job
1Scheduled Task
1Replay Monitor
Loading Replay Monitor...
Downloads
tmpC2F8.tmp.exe
MasonClient.exe
memory/2808-11-0x00007FFA83520000-0x00007FFA83EC4000-memory.dmp
memory/2808-12-0x00007FFA83520000-0x00007FFA83EC4000-memory.dmp
memory/2808-5-0x000000001B1A0000-0x000000001B1B4000-memory.dmp
memory/2808-6-0x00007FFA83520000-0x00007FFA83EC4000-memory.dmp
memory/2808-7-0x00007FFA83520000-0x00007FFA83EC4000-memory.dmp
memory/2808-8-0x00007FFA83520000-0x00007FFA83EC4000-memory.dmp
memory/2808-9-0x00007FFA83520000-0x00007FFA83EC4000-memory.dmp
memory/2808-10-0x00007FFA83520000-0x00007FFA83EC4000-memory.dmp
memory/2808-0-0x00000000004B0000-0x00000000004CC000-memory.dmp
memory/2808-4-0x00007FFA83520000-0x00007FFA83EC4000-memory.dmp
memory/2808-1-0x00000000025D0000-0x00000000025E5000-memory.dmp
memory/2808-17-0x00007FFA83520000-0x00007FFA83EC4000-memory.dmp
memory/2808-18-0x00007FFA83520000-0x00007FFA83EC4000-memory.dmp
memory/2808-34-0x0000000000BF0000-0x0000000000BF8000-memory.dmp
memory/2808-20-0x00007FFA83520000-0x00007FFA83EC4000-memory.dmp
memory/2808-3-0x00007FFA836AF000-0x00007FFA836B0000-memory.dmp
memory/5064-19-0x00007FFA83520000-0x00007FFA83EC4000-memory.dmp
memory/5184-33-0x0000000000AB0000-0x0000000000ABA000-memory.dmp