c6dda31fa6cb4ce140f62c9ce604672fa4a9ba5d1792f2d77f3cfcb43b3227ac

max time kernel
94s
max time network
147s
platform
windows10-2004_x64
resource
win10v2004-20221111-en
resource tags

arch:x64arch:x86image:win10v2004-20221111-enlocale:en-usos:windows10-2004-x64system
submitted
14-02-2023 16:10

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General

Target

RustExternal_nls.exe
Size

658KB
MD5

1ab8dbca5e2bba39723f00907d266de7
SHA1

729cb808637568f20ac886b3fac5f3cf5ff01dee
SHA256

c6dda31fa6cb4ce140f62c9ce604672fa4a9ba5d1792f2d77f3cfcb43b3227ac
SHA512

d1a31848eb9b683793afd36031ef8078ff962c2526272782cf2fca8db11afb71643a46b9ad6bce3ba8dba1b638672205726f6e96c7dd3e887228a2368ec08081
SSDEEP

12288:3oSO5i2eVUIvybKcEz4MM7S9HdKINesX7j6p9PI8GS0oN2:3ouTVUIvtH4H7aLeO23gRoY

Score

7^/10

upx

Malware Config

Signatures

Checks computer location settings 2 TTPs 1 IoCs

Looks up country code configured in the registry, likely geofence.

Query Registry

T1012

System Information Discovery

T1082

description	ioc	Process
Key value queried	\REGISTRY\USER\S-1-5-21-4246620582-653642754-1174164128-1000\Control Panel\International\Geo\Nation	RegAsm.exe

Executes dropped EXE 1 IoCs

pid	Process
4580	DEFENDERFILESECURITY.EXE

UPX packed file 4 IoCs

Detects executables packed with UPX/modified UPX open source packer.

upx

resource	yara_rule
behavioral2/files/0x000900000002317b-141.dat	upx
behavioral2/files/0x000900000002317b-142.dat	upx
behavioral2/memory/4580-144-0x00007FF656DE0000-0x00007FF656F3F000-memory.dmp	upx
behavioral2/memory/4580-146-0x00007FF656DE0000-0x00007FF656F3F000-memory.dmp	upx

Suspicious use of SetThreadContext 1 IoCs

description	pid	Process	procid_target
PID 4872 set thread context of 4764	4872	RustExternal_nls.exe	80

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

System Information Discovery
T1082

Modifies registry class 2 IoCs

description	ioc	Process
Key created	\REGISTRY\USER\S-1-5-21-4246620582-653642754-1174164128-1000_Classes\Local Settings	RegAsm.exe
Key created	\REGISTRY\USER\S-1-5-21-4246620582-653642754-1174164128-1000_Classes\Local Settings	OpenWith.exe

Suspicious behavior: EnumeratesProcesses 2 IoCs

pid	Process
4872	RustExternal_nls.exe
4872	RustExternal_nls.exe

Suspicious use of AdjustPrivilegeToken 1 IoCs

description	pid	Process
Token: SeDebugPrivilege	4872	RustExternal_nls.exe

Suspicious use of SetWindowsHookEx 1 IoCs

pid	Process
4576	OpenWith.exe

Suspicious use of WriteProcessMemory 17 IoCs

description	pid	Process	procid_target
PID 4872 wrote to memory of 4824	4872	RustExternal_nls.exe	79
PID 4872 wrote to memory of 4824	4872	RustExternal_nls.exe	79
PID 4872 wrote to memory of 4824	4872	RustExternal_nls.exe	79
PID 4872 wrote to memory of 4764	4872	RustExternal_nls.exe	80
PID 4872 wrote to memory of 4764	4872	RustExternal_nls.exe	80
PID 4872 wrote to memory of 4764	4872	RustExternal_nls.exe	80
PID 4872 wrote to memory of 4764	4872	RustExternal_nls.exe	80
PID 4872 wrote to memory of 4764	4872	RustExternal_nls.exe	80
PID 4872 wrote to memory of 4764	4872	RustExternal_nls.exe	80
PID 4872 wrote to memory of 4764	4872	RustExternal_nls.exe	80
PID 4872 wrote to memory of 4764	4872	RustExternal_nls.exe	80
PID 4872 wrote to memory of 4764	4872	RustExternal_nls.exe	80
PID 4872 wrote to memory of 4764	4872	RustExternal_nls.exe	80
PID 4764 wrote to memory of 4580	4764	RegAsm.exe	81
PID 4764 wrote to memory of 4580	4764	RegAsm.exe	81
PID 4580 wrote to memory of 1036	4580	DEFENDERFILESECURITY.EXE	87
PID 4580 wrote to memory of 1036	4580	DEFENDERFILESECURITY.EXE	87

C:\Users\Admin\AppData\Local\Temp\RustExternal_nls.exe
"C:\Users\Admin\AppData\Local\Temp\RustExternal_nls.exe"
1⤵
- Suspicious use of SetThreadContext
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:4872
- C:\Windows\Microsoft.NET\Framework\v4.0.30319\RegAsm.exe
  #cmd
  2⤵
  PID:4824
- C:\Windows\Microsoft.NET\Framework\v4.0.30319\RegAsm.exe
  #cmd
  2⤵
  - Checks computer location settings
  - Modifies registry class
  - Suspicious use of WriteProcessMemory
  PID:4764
- - C:\Users\Admin\AppData\Roaming\DEFENDERFILESECURITY.EXE
    "C:\Users\Admin\AppData\Roaming\DEFENDERFILESECURITY.EXE"
    3⤵
    - Executes dropped EXE
    - Suspicious use of WriteProcessMemory
    PID:4580
  - - C:\Windows\system32\cmd.exe
      "cmd" /C C:\Users\Admin\AppData\Local\Temp\0.exe
      4⤵
      PID:1036

C:\Windows\system32\OpenWith.exe
C:\Windows\system32\OpenWith.exe -Embedding
1⤵
- Modifies registry class
- Suspicious use of SetWindowsHookEx
PID:4576

Network

MITRE ATT&CK Enterprise v6

Initial Access

Execution

Persistence

Privilege Escalation

Defense Evasion

Credential Access

Discovery

Query Registry

T1012

System Information Discovery

T1082

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

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Downloads

C:\Users\Admin\AppData\Local\Temp\0.exe

Filesize
298B

MD5
3861a3795095fe81fcb8382d2b9066bd

SHA1
2cef2af9a35d636c3af48902c20891ec49a8e791

SHA256
b19463cb9b847bdfc7dbf8133d9702d0a0ecc4175335c4a75db211e0196f84b3

SHA512
8e881d7f7a8236d36aef500473a3dbc5a98d46c1596d33ab76e4669f858d86c6b4881c0882c37d2d32b888fcaf6280385932ca5ffc6a5143d625c71b8fc8b294

Download Submit
C:\Users\Admin\AppData\Roaming\DEFENDERFILESECURITY.EXE

Filesize
532KB

MD5
84e6aa267c6970d2d777d60840390102

SHA1
c97e555e98c5bec69bcad9607cf0153ff827a141

SHA256
69f7c84e27083e5af30a91c797c6c1d5b694c2926ebb8a9edb7c6ed8e4c3cb3c

SHA512
47184ca58f7358bad24acbcfc2038a510a1ae55b90b927d79a98df13c0e911daeaadb1100f0dc112370fe61bf6264fb9ff214d143d17af659e0bd1ba16f0cecc

Download Submit
C:\Users\Admin\AppData\Roaming\DEFENDERFILESECURITY.EXE

Filesize
532KB

MD5
84e6aa267c6970d2d777d60840390102

SHA1
c97e555e98c5bec69bcad9607cf0153ff827a141

SHA256
69f7c84e27083e5af30a91c797c6c1d5b694c2926ebb8a9edb7c6ed8e4c3cb3c

SHA512
47184ca58f7358bad24acbcfc2038a510a1ae55b90b927d79a98df13c0e911daeaadb1100f0dc112370fe61bf6264fb9ff214d143d17af659e0bd1ba16f0cecc

Download Submit
memory/4580-146-0x00007FF656DE0000-0x00007FF656F3F000-memory.dmp

Filesize
1.4MB

Download
memory/4580-144-0x00007FF656DE0000-0x00007FF656F3F000-memory.dmp

Filesize
1.4MB

Download
memory/4764-135-0x0000000000400000-0x0000000000497000-memory.dmp

Filesize
604KB

Download
memory/4764-139-0x0000000000400000-0x0000000000497000-memory.dmp

Filesize
604KB

Download
memory/4764-137-0x0000000000400000-0x0000000000497000-memory.dmp

Filesize
604KB

Download
memory/4764-143-0x0000000000400000-0x0000000000497000-memory.dmp

Filesize
604KB

Download
memory/4764-136-0x0000000000400000-0x0000000000497000-memory.dmp

Filesize
604KB

Download
memory/4872-132-0x0000000000E10000-0x0000000000EBA000-memory.dmp

Filesize
680KB

Download