asyncrat | 24fa23a1908d5afe4a323872a2df703ecdc1fe033d321423c6c60f983d8d1f6e

General

Target

AsyncClient.exe
Size

45KB
MD5

2f0206e9dd15d9dccb2ecf93e7cf8ce8
SHA1

48223ea372b29b082e8f44c610ffc0edd88ed2ae
SHA256

24fa23a1908d5afe4a323872a2df703ecdc1fe033d321423c6c60f983d8d1f6e
SHA512

0790798f4a11cbf09c2a1dc74ef92c1b2f84c3b659efec9df9099a1eaab9c6a00c430c8316aaefa94da206b589741c45e7f0bf56cd3b58e8e43f8a8130ff8160
SSDEEP

768:puwpFTAY3IQWUe9jqmo2qLoKjPGaG6PIyzjbFgX3i+7Qs0M48wDdOTwBDZ6x:puwpFTA4/2xKTkDy3bCXS+cs07tgmd6x

Score

10^/10

asyncrat default discovery rat

Malware Config

Extracted

Family

asyncrat

Version

0.5.8

Botnet

Default

C2

127.0.0.1:6606

127.0.0.1:7707

127.0.0.1:8808

Mutex

ZC7aTuQsZ3YU

Attributes

delay
3
install
true
install_file
new rat.exe
install_folder
%AppData%

aes.plain

Signatures

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

Async RAT payload 1 IoCs

rat

resource	yara_rule
behavioral2/files/0x000b0000000233e9-11.dat	family_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	AsyncClient.exe

Executes dropped EXE 1 IoCs

pid	Process
4828	new rat.exe

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

System Information Discovery
T1082

System Location Discovery: System Language Discovery 1 TTPs 6 IoCs

Attempt gather information about the system language of a victim in order to infer the geographical location of that host.

discovery

System Language Discovery

T1614.001

description	ioc	Process
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	cmd.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	timeout.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	schtasks.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	new rat.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	AsyncClient.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	cmd.exe

Delays execution with timeout.exe 1 IoCs

evasion

pid	Process
2832	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
4016	schtasks.exe

Suspicious behavior: EnumeratesProcesses 21 IoCs

pid	Process
2592	AsyncClient.exe
2592	AsyncClient.exe
2592	AsyncClient.exe
2592	AsyncClient.exe
2592	AsyncClient.exe
2592	AsyncClient.exe
2592	AsyncClient.exe
2592	AsyncClient.exe
2592	AsyncClient.exe
2592	AsyncClient.exe
2592	AsyncClient.exe
2592	AsyncClient.exe
2592	AsyncClient.exe
2592	AsyncClient.exe
2592	AsyncClient.exe
2592	AsyncClient.exe
2592	AsyncClient.exe
2592	AsyncClient.exe
2592	AsyncClient.exe
2592	AsyncClient.exe
2592	AsyncClient.exe

Suspicious use of AdjustPrivilegeToken 2 IoCs

description	pid	Process
Token: SeDebugPrivilege	2592	AsyncClient.exe
Token: SeDebugPrivilege	4828	new rat.exe

Suspicious use of WriteProcessMemory 15 IoCs

description	pid	Process	procid_target
PID 2592 wrote to memory of 1516	2592	AsyncClient.exe	88
PID 2592 wrote to memory of 1516	2592	AsyncClient.exe	88
PID 2592 wrote to memory of 1516	2592	AsyncClient.exe	88
PID 2592 wrote to memory of 1720	2592	AsyncClient.exe	90
PID 2592 wrote to memory of 1720	2592	AsyncClient.exe	90
PID 2592 wrote to memory of 1720	2592	AsyncClient.exe	90
PID 1720 wrote to memory of 2832	1720	cmd.exe	92
PID 1720 wrote to memory of 2832	1720	cmd.exe	92
PID 1720 wrote to memory of 2832	1720	cmd.exe	92
PID 1516 wrote to memory of 4016	1516	cmd.exe	93
PID 1516 wrote to memory of 4016	1516	cmd.exe	93
PID 1516 wrote to memory of 4016	1516	cmd.exe	93
PID 1720 wrote to memory of 4828	1720	cmd.exe	94
PID 1720 wrote to memory of 4828	1720	cmd.exe	94
PID 1720 wrote to memory of 4828	1720	cmd.exe	94

C:\Users\Admin\AppData\Local\Temp\AsyncClient.exe
"C:\Users\Admin\AppData\Local\Temp\AsyncClient.exe"
1⤵
- Checks computer location settings
- System Location Discovery: System Language Discovery
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:2592
- C:\Windows\SysWOW64\cmd.exe
  "C:\Windows\System32\cmd.exe" /c schtasks /create /f /sc onlogon /rl highest /tn "new rat" /tr '"C:\Users\Admin\AppData\Roaming\new rat.exe"' & exit
  2⤵
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:1516
- - C:\Windows\SysWOW64\schtasks.exe
    schtasks /create /f /sc onlogon /rl highest /tn "new rat" /tr '"C:\Users\Admin\AppData\Roaming\new rat.exe"'
    3⤵
    - System Location Discovery: System Language Discovery
    - Scheduled Task/Job: Scheduled Task
    PID:4016
- C:\Windows\SysWOW64\cmd.exe
  C:\Windows\system32\cmd.exe /c ""C:\Users\Admin\AppData\Local\Temp\tmp8C04.tmp.bat""
  2⤵
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:1720
- - C:\Windows\SysWOW64\timeout.exe
    timeout 3
    3⤵
    - System Location Discovery: System Language Discovery
    - Delays execution with timeout.exe
    PID:2832
- - C:\Users\Admin\AppData\Roaming\new rat.exe
    "C:\Users\Admin\AppData\Roaming\new rat.exe"
    3⤵
    - Executes dropped EXE
    - System Location Discovery: System Language Discovery
    - Suspicious use of AdjustPrivilegeToken
    PID:4828

C:\Windows\System32\rundll32.exe
C:\Windows\System32\rundll32.exe C:\Windows\System32\shell32.dll,SHCreateLocalServerRunDll {9aa46009-3ce0-458a-a354-715610a075e6} -Embedding
1⤵
PID:2460

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Persistence

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Privilege Escalation

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Defense Evasion

Credential Access

Discovery

Query Registry

1

T1012

System Information Discovery

2

T1082

System Location Discovery

1

T1614

System Language Discovery

1

T1614.001

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

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Downloads

C:\Users\Admin\AppData\Local\Temp\tmp8C04.tmp.bat

Filesize
151B

MD5
12b4696f0c058063e5d32408cb159b9e

SHA1
8367be0efe4a336d448ba28871ca227f09f101ee

SHA256
d74d27bc013aa1b6d134918a615df2cd5986622264bdb00fbcdcc0592efaf14b

SHA512
41cf08f3050d240f80c832894d79ca5710938cf7334d9b86140e9f452be684181e2057d852f50aa6c53f97aa204c633cc93dab7f737040a44420b2d48ff5e242

Download Submit
C:\Users\Admin\AppData\Roaming\new rat.exe

Filesize
45KB

MD5
2f0206e9dd15d9dccb2ecf93e7cf8ce8

SHA1
48223ea372b29b082e8f44c610ffc0edd88ed2ae

SHA256
24fa23a1908d5afe4a323872a2df703ecdc1fe033d321423c6c60f983d8d1f6e

SHA512
0790798f4a11cbf09c2a1dc74ef92c1b2f84c3b659efec9df9099a1eaab9c6a00c430c8316aaefa94da206b589741c45e7f0bf56cd3b58e8e43f8a8130ff8160

Download Submit
memory/2592-0-0x000000007520E000-0x000000007520F000-memory.dmp

Filesize
4KB

Download
memory/2592-1-0x0000000000020000-0x0000000000032000-memory.dmp

Filesize
72KB

Download
memory/2592-2-0x0000000075200000-0x00000000759B0000-memory.dmp

Filesize
7.7MB

Download
memory/2592-3-0x00000000049E0000-0x0000000004A7C000-memory.dmp

Filesize
624KB

Download
memory/2592-8-0x0000000075200000-0x00000000759B0000-memory.dmp

Filesize
7.7MB

Download
memory/4828-13-0x0000000075200000-0x00000000759B0000-memory.dmp

Filesize
7.7MB

Download
memory/4828-14-0x0000000075200000-0x00000000759B0000-memory.dmp

Filesize
7.7MB

Download

Analysis

Sharing

General

Malware Config

Extracted

Signatures

Processes

Network

MITRE ATT&CK Enterprise v15

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Downloads