asyncrat | 7559e6ca8b77400f88bf4e67208a1c32570a670068eccae9e3d226cc5471bd47

Analysis

max time kernel
149s
max time network
158s
platform
windows10-2004_x64
resource
win10v2004-20240802-en
resource tags

arch:x64arch:x86image:win10v2004-20240802-enlocale:en-usos:windows10-2004-x64system
submitted
17-09-2024 06:30

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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-1-5-21-4182098368-2521458979-3782681353-1000\Control Panel\International\Geo\Nation	HEUR-Backdoor.MSIL.Crysan.exe

Executes dropped EXE 1 IoCs

pid	Process
3568	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
2124	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
404	schtasks.exe

Suspicious behavior: EnumeratesProcesses 24 IoCs

pid	Process
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
4508	HEUR-Backdoor.MSIL.Crysan.exe
3568	Boomi.exe

Suspicious use of AdjustPrivilegeToken 2 IoCs

description	pid	Process
Token: SeDebugPrivilege	4508	HEUR-Backdoor.MSIL.Crysan.exe
Token: SeDebugPrivilege	3568	Boomi.exe

Suspicious use of WriteProcessMemory 8 IoCs

description	pid	Process	procid_target
PID 4508 wrote to memory of 404	4508	HEUR-Backdoor.MSIL.Crysan.exe	88
PID 4508 wrote to memory of 404	4508	HEUR-Backdoor.MSIL.Crysan.exe	88
PID 4508 wrote to memory of 4224	4508	HEUR-Backdoor.MSIL.Crysan.exe	90
PID 4508 wrote to memory of 4224	4508	HEUR-Backdoor.MSIL.Crysan.exe	90
PID 4224 wrote to memory of 2124	4224	cmd.exe	92
PID 4224 wrote to memory of 2124	4224	cmd.exe	92
PID 4224 wrote to memory of 3568	4224	cmd.exe	93
PID 4224 wrote to memory of 3568	4224	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:4508
- 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:404
- C:\Windows\system32\cmd.exe
  C:\Windows\system32\cmd.exe /c ""C:\Users\Admin\AppData\Local\Temp\tmpBC89.tmp.bat""
  2⤵
  - Suspicious use of WriteProcessMemory
  PID:4224
- - C:\Windows\system32\timeout.exe
    timeout 3
    3⤵
    - Delays execution with timeout.exe
    PID:2124
- - 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:3568

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\tmpBC89.tmp.bat

Filesize
149B

MD5
e9aa8ba9b9fbccfde71edfa00d53c5a0

SHA1
b98ece4b43d6557adc702b12a7cac6915e1f9618

SHA256
181adfedc5e4b292497428806707ca53ce296205d3f9334aaa50661064a90e57

SHA512
64fc2dd694ee6c064ed89d5744fa6007484ba9626be6d498d58303ab5633a3fb95cdf2782523818ae91e8febdafa67e11df168247df1aeda02258125403924f8

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

Filesize
43.9MB

MD5
4837a99a273e05c215185fd86916f8a5

SHA1
4436bc59ac6a2f63f5a4f35f935551fbe75f445e

SHA256
1ff968888fcad7e69ebc02b01e0da2d4450766d667d65bbf4b96f86886009c1d

SHA512
23eaac6e10bfd1b420991608741c61baccd144e74e699b2f8893aff07f38b4a76f4b7bfbdb93c8d7add46a02ce4fcb254ab183958b50c533109d181eb97c15cb

Download Submit
memory/3568-14-0x00007FFA14ED0000-0x00007FFA15991000-memory.dmp

Filesize
10.8MB

Download
memory/3568-15-0x00007FFA14ED0000-0x00007FFA15991000-memory.dmp

Filesize
10.8MB

Download
memory/4508-1-0x0000000000400000-0x0000000000412000-memory.dmp

Filesize
72KB

Download
memory/4508-0-0x00007FFA14ED3000-0x00007FFA14ED5000-memory.dmp

Filesize
8KB

Download
memory/4508-2-0x00007FFA14ED0000-0x00007FFA15991000-memory.dmp

Filesize
10.8MB

Download
memory/4508-3-0x00007FFA14ED3000-0x00007FFA14ED5000-memory.dmp

Filesize
8KB

Download
memory/4508-4-0x00007FFA14ED0000-0x00007FFA15991000-memory.dmp

Filesize
10.8MB

Download
memory/4508-10-0x00007FFA14ED0000-0x00007FFA15991000-memory.dmp

Filesize
10.8MB

Download