asyncrat | e544ff3ed62db97c02442c849b3214a7b3d913fb73b430d79edf557e7ec91555

General

Target

AsyncClient.exe
Size

47KB
MD5

c792e7efbdb2d57c605efcb45a48109d
SHA1

eb0c663a68aee213c6b64e1f10207409f0da5b20
SHA256

e544ff3ed62db97c02442c849b3214a7b3d913fb73b430d79edf557e7ec91555
SHA512

f407285fd965f6d7e5ea42312fda6159cd9546480e2752983cf6f784c414ee040446c6bbb595d27e9d27d07e5f59355265fe7384f6666af86c3c6a8e1aa74b33
SSDEEP

768:Juk0VT3ongoWU2Gjimo2qryBmv83OxmIsPIjACXD9izQ0b3eQbC2l6S6heyV27H1:Juk0VT3Q+2qg0jAgCb3ZbC2lqYyV27hv

Score

10^/10

asyncrat default discovery rat

Malware Config

Extracted

Family

asyncrat

Version

0.5.8

Botnet

Default

C2

127.0.0.1:7707

127.0.0.1:8808

Mutex

uSyaMxhmF1LU

Attributes

delay
3
install
true
install_file
hey.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/0x0005000000022a80-11.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
5080	hey.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	timeout.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	hey.exe
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	schtasks.exe

Delays execution with timeout.exe 1 IoCs

evasion

pid	Process
2784	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
4208	schtasks.exe

Suspicious behavior: EnumeratesProcesses 23 IoCs

pid	Process
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe
468	AsyncClient.exe

Suspicious use of AdjustPrivilegeToken 3 IoCs

description	pid	Process
Token: SeDebugPrivilege	468	AsyncClient.exe
Token: SeDebugPrivilege	5080	hey.exe
Token: SeDebugPrivilege	5080	hey.exe

Suspicious use of WriteProcessMemory 15 IoCs

description	pid	Process	procid_target
PID 468 wrote to memory of 688	468	AsyncClient.exe	91
PID 468 wrote to memory of 688	468	AsyncClient.exe	91
PID 468 wrote to memory of 688	468	AsyncClient.exe	91
PID 468 wrote to memory of 2520	468	AsyncClient.exe	93
PID 468 wrote to memory of 2520	468	AsyncClient.exe	93
PID 468 wrote to memory of 2520	468	AsyncClient.exe	93
PID 688 wrote to memory of 4208	688	cmd.exe	95
PID 688 wrote to memory of 4208	688	cmd.exe	95
PID 688 wrote to memory of 4208	688	cmd.exe	95
PID 2520 wrote to memory of 2784	2520	cmd.exe	96
PID 2520 wrote to memory of 2784	2520	cmd.exe	96
PID 2520 wrote to memory of 2784	2520	cmd.exe	96
PID 2520 wrote to memory of 5080	2520	cmd.exe	101
PID 2520 wrote to memory of 5080	2520	cmd.exe	101
PID 2520 wrote to memory of 5080	2520	cmd.exe	101

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:468
- C:\Windows\SysWOW64\cmd.exe
  "C:\Windows\System32\cmd.exe" /c schtasks /create /f /sc onlogon /rl highest /tn "hey" /tr '"C:\Users\Admin\AppData\Roaming\hey.exe"' & exit
  2⤵
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:688
- - C:\Windows\SysWOW64\schtasks.exe
    schtasks /create /f /sc onlogon /rl highest /tn "hey" /tr '"C:\Users\Admin\AppData\Roaming\hey.exe"'
    3⤵
    - System Location Discovery: System Language Discovery
    - Scheduled Task/Job: Scheduled Task
    PID:4208
- C:\Windows\SysWOW64\cmd.exe
  C:\Windows\system32\cmd.exe /c ""C:\Users\Admin\AppData\Local\Temp\tmpC582.tmp.bat""
  2⤵
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:2520
- - C:\Windows\SysWOW64\timeout.exe
    timeout 3
    3⤵
    - System Location Discovery: System Language Discovery
    - Delays execution with timeout.exe
    PID:2784
- - C:\Users\Admin\AppData\Roaming\hey.exe
    "C:\Users\Admin\AppData\Roaming\hey.exe"
    3⤵
    - Executes dropped EXE
    - System Location Discovery: System Language Discovery
    - Suspicious use of AdjustPrivilegeToken
    PID:5080

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\tmpC582.tmp.bat

Filesize
147B

MD5
154dcc6f699244c197836b0abc1c14f9

SHA1
8bf6b4981a190b79f7ece2aa0bd9eb5111bc53a9

SHA256
f47cb920a4e55aeb48c195385da84915ca43aa299ca567ae1498e35584f4af1d

SHA512
bc86d1bf6d46647ff46c88a875874d4945188d8a9c8843a530ec455c69e50ffc232863a82d4b3f8c0c44f7b78ea97bd314eb7e7b91122d78bc6acf39bc3dae63

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

Filesize
47KB

MD5
c792e7efbdb2d57c605efcb45a48109d

SHA1
eb0c663a68aee213c6b64e1f10207409f0da5b20

SHA256
e544ff3ed62db97c02442c849b3214a7b3d913fb73b430d79edf557e7ec91555

SHA512
f407285fd965f6d7e5ea42312fda6159cd9546480e2752983cf6f784c414ee040446c6bbb595d27e9d27d07e5f59355265fe7384f6666af86c3c6a8e1aa74b33

Download Submit
memory/468-0-0x0000000074CFE000-0x0000000074CFF000-memory.dmp

Filesize
4KB

Download
memory/468-1-0x0000000000E80000-0x0000000000E92000-memory.dmp

Filesize
72KB

Download
memory/468-2-0x0000000074CF0000-0x00000000754A0000-memory.dmp

Filesize
7.7MB

Download
memory/468-3-0x00000000058D0000-0x000000000596C000-memory.dmp

Filesize
624KB

Download
memory/468-8-0x0000000074CF0000-0x00000000754A0000-memory.dmp

Filesize
7.7MB

Download
memory/5080-13-0x0000000074C40000-0x00000000753F0000-memory.dmp

Filesize
7.7MB

Download
memory/5080-14-0x0000000074C40000-0x00000000753F0000-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