Analysis
- max time kernel
149s - max time network
148s - platform
windows11-21h2_x64 - resource
win11-20260911-en - resource tags
arch:x64arch:x86image:win11-20260911-enlocale:en-usos:windows11-21h2-x64systemwindows - submitted
23/09/2026, 23:38
Behavioral task
behavioral1
Sample
MasonClient.exe
Resource
win10v2004-20260911-en
Behavioral task
behavioral2
Sample
MasonClient.exe
Resource
win10ltsc2021-20260911-en
Behavioral task
behavioral3
Sample
MasonClient.exe
Resource
win11-20260911-en
Behavioral task
behavioral4
Sample
MasonClient.exe
Resource
win11ltsc2024-20260911-en
General
- Target MasonClient.exe
- Size 48KB
- Sample260923-3m4zmsgc95
- SHA256 b9cdd113799ba3b6f22bc5ed593a71a61f37429b14af020a2acbed2eab6686a8
- MD5 e85edb5b4419933ff4fc1063cb8ed87d
- SHA1 5beb0a7e267da66c8648dd8f69e4b845a7eb12e5
- SHA512 2202baae2c33e05f13c59c916b0de348e23dd5017f62c8ed6637fa476689c9d2e4b8a7a885ffb74f7e61847dd21f2aaa7f5d6221ae49b3ddaa9566554b4657da
- SSDEEP 768:HoqBK+AEqgvHyzw2Prth9sLZZI4bYlnggUNcgGhLOHOYD:HoqBxLvEw2BcZbYlnBld1OuYD
- TLSH T1A123C48DBBE40129D5BE5BF16D73A209C3B079939506C60FACD402CB2B677984691EF3
- MD5 SHA1 SHA512 SSDEEP TLSH
Malware Config
Extracted
-
neptunerat
-
h2ackercypranos-49474.portmap.host:49474
-
filename
USB.exe
-
group
MasonGroup
-
key
OWKlVlNZmydAbDUL
-
rat_name
MasonRAT
Signatures
- Family: NeptuneRAT, MasonRAT
NeptuneRAT aka MasonRAT is a trojan written in C#.
- Detects NeptuneRAT stealer 2 IoCs
resource yara_rule behavioral3/memory/4128-0-0x00000000002E0000-0x00000000002F2000-memory.dmp family_neptunerat behavioral3/files/0x0016000000025a12-3.dat family_neptunerat - Executes dropped EXE 4 IoCs
pid Process 4068 MasonClient.exe 784 MasonClient.exe 1704 MasonClient.exe 4588 MasonClient.exe - Enumerates physical storage devices 1 TTPs
Attempts to interact with connected storage/optical drive(s).
- Scheduled Task/Job: Scheduled Task 1 TTPs 1 IoCs
Schtasks is often used by malware for persistence or to perform post-infection execution.
pid Process 2996 schtasks.exe - Suspicious use of AdjustPrivilegeToken 5 IoCs
description pid Process Token: SeDebugPrivilege 4128 MasonClient.exe Token: SeDebugPrivilege 4068 MasonClient.exe Token: SeDebugPrivilege 784 MasonClient.exe Token: SeDebugPrivilege 1704 MasonClient.exe Token: SeDebugPrivilege 4588 MasonClient.exe - Suspicious use of WriteProcessMemory 1 IoCs
description pid Process procid_target PID 4128 wrote to memory of 2996 4128 MasonClient.exe 80 - 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⤵
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:4128 -
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
PID:2996
-
-
C:\Users\Admin\AppData\Roaming\MasonClient.exeC:\Users\Admin\AppData\Roaming\MasonClient.exe1⤵
- Executes dropped EXE
- Suspicious use of AdjustPrivilegeToken
PID:4068
-
C:\Users\Admin\AppData\Roaming\MasonClient.exeC:\Users\Admin\AppData\Roaming\MasonClient.exe1⤵
- Executes dropped EXE
- Suspicious use of AdjustPrivilegeToken
PID:784
-
C:\Users\Admin\AppData\Roaming\MasonClient.exeC:\Users\Admin\AppData\Roaming\MasonClient.exe1⤵
- Executes dropped EXE
- Suspicious use of AdjustPrivilegeToken
PID:1704
-
C:\Users\Admin\AppData\Roaming\MasonClient.exeC:\Users\Admin\AppData\Roaming\MasonClient.exe1⤵
- Executes dropped EXE
- Suspicious use of AdjustPrivilegeToken
PID:4588
Network
MITRE ATT&CK Enterprise v16
Replay Monitor
Loading Replay Monitor...
Downloads
- Path C:\Users\Admin\AppData\Local\Microsoft\CLR_v4.0\UsageLogs\MasonClient.exe.log
- Size 654B
- SHA256 e31b18f21621d9983bfdf1ea3e53884a9d58b8ffd79e0e5790da6f3a81a8b9d3
- MD5 2cbbb74b7da1f720b48ed31085cbd5b8
- SHA1 79caa9a3ea8abe1b9c4326c3633da64a5f724964
- SHA512 ecf02d5240e0c1c005d3ab393aa7eff62bd498c2db5905157e2bf6d29e1b663228a9583950842629d1a4caef404c8941a0c7799b1a3bd1eb890a09fdb7efcff9
- TLSH T119F0A2302371E1C8C9263F422C0D2A4966AF474A7B50FE0C7694635DD825167AF313F3
- MD5 SHA1 SHA512 TLSH
- Path C:\Users\Admin\AppData\Roaming\MasonClient.exe
- Size 48KB
- SHA256 b9cdd113799ba3b6f22bc5ed593a71a61f37429b14af020a2acbed2eab6686a8
- MD5 e85edb5b4419933ff4fc1063cb8ed87d
- SHA1 5beb0a7e267da66c8648dd8f69e4b845a7eb12e5
- SHA512 2202baae2c33e05f13c59c916b0de348e23dd5017f62c8ed6637fa476689c9d2e4b8a7a885ffb74f7e61847dd21f2aaa7f5d6221ae49b3ddaa9566554b4657da
- SSDEEP 768:HoqBK+AEqgvHyzw2Prth9sLZZI4bYlnggUNcgGhLOHOYD:HoqBxLvEw2BcZbYlnBld1OuYD
- TLSH T1A123C48DBBE40129D5BE5BF16D73A209C3B079939506C60FACD402CB2B677984691EF3
- MD5 SHA1 SHA512 SSDEEP TLSH