asyncrat | b7a9152f897cb11101d370f3b1ef30d411d4e4116a57ef31d340a58952cf4c1c

General

Target

AsyncClient.exe
Size

52KB
MD5

422b49a2404d8e67c9cd57d46acc97d0
SHA1

89ca4038856c67d12d31750a799aa88b08acfb82
SHA256

b7a9152f897cb11101d370f3b1ef30d411d4e4116a57ef31d340a58952cf4c1c
SHA512

2d9a65aacce93def1829971071b3c02c64555c0e30deca5ff8b12d04202e4b0a5e85cce8c7e61dfad1d966fe027086e7d18e1bf1c23dbe9695f2a8e082fdc77c
SSDEEP

1536:Ou4X9Tswb2vOnZH4fAzb03lKuIvLZQ7dqx:Ou4tTswb2vOnZH4fAb038L+7wx

Score

10^/10

asyncrat default discovery rat

Malware Config

Extracted

Family

asyncrat

Version

0.5.8

Botnet

Default

C2

x5sql-62870.portmap.host:62870

Mutex

c2VJpocLoXmn

Attributes

delay
3
install
true
install_file
Defender.exe
install_folder
%AppData%

aes.plain

Signatures

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

Async RAT payload 1 IoCs

rat

resource	yara_rule
behavioral2/files/0x0009000000023c4e-12.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-1-5-21-3756129449-3121373848-4276368241-1000\Control Panel\International\Geo\Nation	AsyncClient.exe

Executes dropped EXE 1 IoCs

pid	Process
2064	Defender.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	AsyncClient.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	cmd.exe
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	Defender.exe

Delays execution with timeout.exe 1 IoCs

evasion

pid	Process
2004	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
3668	schtasks.exe

Suspicious behavior: EnumeratesProcesses 23 IoCs

pid	Process
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe
344	AsyncClient.exe

Suspicious use of AdjustPrivilegeToken 3 IoCs

description	pid	Process
Token: SeDebugPrivilege	344	AsyncClient.exe
Token: SeDebugPrivilege	2064	Defender.exe
Token: SeDebugPrivilege	2064	Defender.exe

Suspicious use of WriteProcessMemory 15 IoCs

description	pid	Process	procid_target
PID 344 wrote to memory of 1388	344	AsyncClient.exe	83
PID 344 wrote to memory of 1388	344	AsyncClient.exe	83
PID 344 wrote to memory of 1388	344	AsyncClient.exe	83
PID 344 wrote to memory of 2956	344	AsyncClient.exe	85
PID 344 wrote to memory of 2956	344	AsyncClient.exe	85
PID 344 wrote to memory of 2956	344	AsyncClient.exe	85
PID 2956 wrote to memory of 2004	2956	cmd.exe	87
PID 2956 wrote to memory of 2004	2956	cmd.exe	87
PID 2956 wrote to memory of 2004	2956	cmd.exe	87
PID 1388 wrote to memory of 3668	1388	cmd.exe	88
PID 1388 wrote to memory of 3668	1388	cmd.exe	88
PID 1388 wrote to memory of 3668	1388	cmd.exe	88
PID 2956 wrote to memory of 2064	2956	cmd.exe	89
PID 2956 wrote to memory of 2064	2956	cmd.exe	89
PID 2956 wrote to memory of 2064	2956	cmd.exe	89

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:344
- C:\Windows\SysWOW64\cmd.exe
  "C:\Windows\System32\cmd.exe" /c schtasks /create /f /sc onlogon /rl highest /tn "Defender" /tr '"C:\Users\Admin\AppData\Roaming\Defender.exe"' & exit
  2⤵
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:1388
- - C:\Windows\SysWOW64\schtasks.exe
    schtasks /create /f /sc onlogon /rl highest /tn "Defender" /tr '"C:\Users\Admin\AppData\Roaming\Defender.exe"'
    3⤵
    - System Location Discovery: System Language Discovery
    - Scheduled Task/Job: Scheduled Task
    PID:3668
- C:\Windows\SysWOW64\cmd.exe
  C:\Windows\system32\cmd.exe /c ""C:\Users\Admin\AppData\Local\Temp\tmp92F9.tmp.bat""
  2⤵
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:2956
- - C:\Windows\SysWOW64\timeout.exe
    timeout 3
    3⤵
    - System Location Discovery: System Language Discovery
    - Delays execution with timeout.exe
    PID:2004
- - C:\Users\Admin\AppData\Roaming\Defender.exe
    "C:\Users\Admin\AppData\Roaming\Defender.exe"
    3⤵
    - Executes dropped EXE
    - System Location Discovery: System Language Discovery
    - Suspicious use of AdjustPrivilegeToken
    PID:2064

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\tmp92F9.tmp.bat

Filesize
152B

MD5
9b80655a644349eecd9708bee92f897a

SHA1
813987760d0918cef819de7e145f002a01f6ff19

SHA256
6bb180a2e75933f9bccb10ce6142b962831985c9c25ff3be5640dc68be28876f

SHA512
d38ca07dfd0e7098be89215c7332e952bf0baf5dd192c7b1f0dc35ce4f1cfc00b519a3257b06dc29dd6e558473b7a89f951faba832e5547296b89bb1d127b582

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

Filesize
52KB

MD5
422b49a2404d8e67c9cd57d46acc97d0

SHA1
89ca4038856c67d12d31750a799aa88b08acfb82

SHA256
b7a9152f897cb11101d370f3b1ef30d411d4e4116a57ef31d340a58952cf4c1c

SHA512
2d9a65aacce93def1829971071b3c02c64555c0e30deca5ff8b12d04202e4b0a5e85cce8c7e61dfad1d966fe027086e7d18e1bf1c23dbe9695f2a8e082fdc77c

Download Submit
memory/344-0-0x000000007536E000-0x000000007536F000-memory.dmp

Filesize
4KB

Download
memory/344-1-0x0000000000870000-0x0000000000882000-memory.dmp

Filesize
72KB

Download
memory/344-2-0x0000000075360000-0x0000000075B10000-memory.dmp

Filesize
7.7MB

Download
memory/344-3-0x0000000005260000-0x00000000052C6000-memory.dmp

Filesize
408KB

Download
memory/344-4-0x00000000056F0000-0x000000000578C000-memory.dmp

Filesize
624KB

Download
memory/344-9-0x0000000075360000-0x0000000075B10000-memory.dmp

Filesize
7.7MB

Download
memory/2064-14-0x00000000752B0000-0x0000000075A60000-memory.dmp

Filesize
7.7MB

Download
memory/2064-15-0x00000000752B0000-0x0000000075A60000-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