asyncrat | 7559e6ca8b77400f88bf4e67208a1c32570a670068eccae9e3d226cc5471bd47

Resubmissions

26-09-2024 06:42

240926-hgnp9ashkk 10

25-09-2024 16:40

240925-t6kwfayfph 10

Analysis

max time kernel
150s
max time network
151s
platform
windows10-2004_x64
resource
win10v2004-20240802-en
resource tags

arch:x64arch:x86image:win10v2004-20240802-enlocale:en-usos:windows10-2004-x64system
submitted
25-09-2024 16:40

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General

Target

bazaar.2020.02/HEUR-Backdoor.MSIL.Crysan.exe
Size

46KB
MD5

b36ed4b297c327eb67746e85fe4434f4
SHA1

7f24843a465e1e811b82a79ced5b071f7350155b
SHA256

0a276fdaf3367ca3fd4cf90eb338dd3d0575ba3979f1bd609ce58e13e2aa0a8e
SHA512

d7002fcabec0e34f5200df23e1ba2b9b840ed502f7b22da9c231613092aa853d8fa1b76b6e934947c13ffbfab5ba49be1c057944c726f9b9cb565470c22c2cbf
SSDEEP

768:YCqJlzbXvMdSXekOicvHk3eHlWMPbPgF0qV1ZGF4G1Pc1pBSDHLw5YI6OC22tYch:YCjCeXvZH0ub4Fr/ZUdW1/uHL06O7Kme

Score

10^/10

asyncrat null rat

Malware Config

Extracted

Family

asyncrat

Version

0.5.6A

Botnet

null

bomi.duckdns.org:8080

Mutex

hutqlynrbwzq

Attributes

delay
5
install
true
install_file
Boomi.exe
install_folder
%AppData%

aes.plain

Signatures

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

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-1-5-21-2392887640-1187051047-2909758433-1000\Control Panel\International\Geo\Nation	HEUR-Backdoor.MSIL.Crysan.exe

Executes dropped EXE 1 IoCs

pid	Process
3052	Boomi.exe

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

System Information Discovery
T1082

Delays execution with timeout.exe 1 IoCs

evasion

pid	Process
4216	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
2596	schtasks.exe

Suspicious behavior: EnumeratesProcesses 24 IoCs

pid	Process
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
2560	HEUR-Backdoor.MSIL.Crysan.exe
3052	Boomi.exe

Suspicious use of AdjustPrivilegeToken 2 IoCs

description	pid	Process
Token: SeDebugPrivilege	2560	HEUR-Backdoor.MSIL.Crysan.exe
Token: SeDebugPrivilege	3052	Boomi.exe

Suspicious use of WriteProcessMemory 8 IoCs

description	pid	Process	procid_target
PID 2560 wrote to memory of 2596	2560	HEUR-Backdoor.MSIL.Crysan.exe	88
PID 2560 wrote to memory of 2596	2560	HEUR-Backdoor.MSIL.Crysan.exe	88
PID 2560 wrote to memory of 2640	2560	HEUR-Backdoor.MSIL.Crysan.exe	90
PID 2560 wrote to memory of 2640	2560	HEUR-Backdoor.MSIL.Crysan.exe	90
PID 2640 wrote to memory of 4216	2640	cmd.exe	92
PID 2640 wrote to memory of 4216	2640	cmd.exe	92
PID 2640 wrote to memory of 3052	2640	cmd.exe	93
PID 2640 wrote to memory of 3052	2640	cmd.exe	93

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.
persistence

Query Registry
T1012

C:\Users\Admin\AppData\Local\Temp\bazaar.2020.02\HEUR-Backdoor.MSIL.Crysan.exe
"C:\Users\Admin\AppData\Local\Temp\bazaar.2020.02\HEUR-Backdoor.MSIL.Crysan.exe"
1⤵
- Checks computer location settings
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:2560
- C:\Windows\System32\schtasks.exe
  "C:\Windows\System32\schtasks.exe" /create /f /sc ONLOGON /RL HIGHEST /tn "'Boomi"' /tr "'C:\Users\Admin\AppData\Roaming\Boomi.exe"'
  2⤵
  - Scheduled Task/Job: Scheduled Task
  PID:2596
- C:\Windows\system32\cmd.exe
  C:\Windows\system32\cmd.exe /c ""C:\Users\Admin\AppData\Local\Temp\tmpD8F1.tmp.bat""
  2⤵
  - Suspicious use of WriteProcessMemory
  PID:2640
- - C:\Windows\system32\timeout.exe
    timeout 3
    3⤵
    - Delays execution with timeout.exe
    PID:4216
- - C:\Users\Admin\AppData\Roaming\Boomi.exe
    "C:\Users\Admin\AppData\Roaming\Boomi.exe"
    3⤵
    - Executes dropped EXE
    - Suspicious behavior: EnumeratesProcesses
    - Suspicious use of AdjustPrivilegeToken
    PID:3052

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

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

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\tmpD8F1.tmp.bat

Filesize
149B

MD5
e62cfacd42e567499a44f6ce12deae25

SHA1
9dbd5186f3d0d600249a413449a8dcf91b150eb7

SHA256
0a539a3e8770fa86f83df33b6e59cb75be36480ec0c683edfc08a57f3ce5fb2a

SHA512
786274d97caf92f529612f744f10cf358377d486d4b9f5491ce04776ec2b2bfc7094a129dee781e72fbeb95e1cbeb7eb976d558496d16f409cc5708039884641

Download Submit
C:\Users\Admin\AppData\Roaming\Boomi.exe

Filesize
42.9MB

MD5
e06963be8a4a7ccce03e5a3f5c4ddeb3

SHA1
74b34cc4554f459838b5f81638b6be9234a49604

SHA256
20d60779484fefafaddcae84b1dc1cb972ff0e6ba2058dd28ac1ead9fa6204f4

SHA512
86af32dbbecded1883c3e9025cce2faa0abb6e89e986d195196672d7274d5a23d8d88738c5cfb34dd5c5c571127f5b12db035d717407f27810080943bf70daf6

Download Submit
memory/2560-0-0x00007FFAF6973000-0x00007FFAF6975000-memory.dmp

Filesize
8KB

Download
memory/2560-1-0x0000000000E20000-0x0000000000E32000-memory.dmp

Filesize
72KB

Download
memory/2560-2-0x00007FFAF6970000-0x00007FFAF7431000-memory.dmp

Filesize
10.8MB

Download
memory/2560-3-0x00007FFAF6973000-0x00007FFAF6975000-memory.dmp

Filesize
8KB

Download
memory/2560-4-0x00007FFAF6970000-0x00007FFAF7431000-memory.dmp

Filesize
10.8MB

Download
memory/2560-10-0x00007FFAF6970000-0x00007FFAF7431000-memory.dmp

Filesize
10.8MB

Download
memory/3052-14-0x00007FFAF6970000-0x00007FFAF7431000-memory.dmp

Filesize
10.8MB

Download
memory/3052-15-0x00007FFAF6970000-0x00007FFAF7431000-memory.dmp

Filesize
10.8MB

Download