asyncrat | 02d242ea2f9251a46c8fc7fdc8a7c00a64491f015b3b8dbe11ff7afaff3fa7c9

General

Target

AsyncClient.exe
Size

45KB
MD5

87b6917db381131a861ba84d4269b0bd
SHA1

801e58b238a02f2d0bb972ee230e77f4bfe4baa1
SHA256

02d242ea2f9251a46c8fc7fdc8a7c00a64491f015b3b8dbe11ff7afaff3fa7c9
SHA512

b297874e06ff77aa8115f9935a7b13fd34a472f904f960708f9c8c86881c6256834362fe8bbdee35914a132d9db4b5fc7f2fb6d418f042cbf5d8a89c5bf5fb6e
SSDEEP

768:/u67dTAYhbJWUh9Nzmo2qLIKjPGaG6PIyzjbFgX3iuzTMsfaP9c9CysmBDZER:/u67dTAur2RKTkDy3bCXSoMWaP9QjdER

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

149.143.127.81:6606

149.143.127.81:7707

149.143.127.81:8808

Mutex

RPDOrlBP5iQP

Attributes

delay
3
install
true
install_file
Update.exe
install_folder
%Temp%

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/0x0009000000023c5a-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
2380	Update.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	schtasks.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	timeout.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	Update.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
5060	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
452	schtasks.exe

Suspicious behavior: EnumeratesProcesses 23 IoCs

pid	Process
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe
2244	AsyncClient.exe

Suspicious use of AdjustPrivilegeToken 3 IoCs

description	pid	Process
Token: SeDebugPrivilege	2244	AsyncClient.exe
Token: SeDebugPrivilege	2380	Update.exe
Token: SeDebugPrivilege	2380	Update.exe

Suspicious use of WriteProcessMemory 15 IoCs

description	pid	Process	procid_target
PID 2244 wrote to memory of 2112	2244	AsyncClient.exe	83
PID 2244 wrote to memory of 2112	2244	AsyncClient.exe	83
PID 2244 wrote to memory of 2112	2244	AsyncClient.exe	83
PID 2244 wrote to memory of 1808	2244	AsyncClient.exe	85
PID 2244 wrote to memory of 1808	2244	AsyncClient.exe	85
PID 2244 wrote to memory of 1808	2244	AsyncClient.exe	85
PID 2112 wrote to memory of 452	2112	cmd.exe	87
PID 2112 wrote to memory of 452	2112	cmd.exe	87
PID 2112 wrote to memory of 452	2112	cmd.exe	87
PID 1808 wrote to memory of 5060	1808	cmd.exe	88
PID 1808 wrote to memory of 5060	1808	cmd.exe	88
PID 1808 wrote to memory of 5060	1808	cmd.exe	88
PID 1808 wrote to memory of 2380	1808	cmd.exe	89
PID 1808 wrote to memory of 2380	1808	cmd.exe	89
PID 1808 wrote to memory of 2380	1808	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:2244
- C:\Windows\SysWOW64\cmd.exe
  "C:\Windows\System32\cmd.exe" /c schtasks /create /f /sc onlogon /rl highest /tn "Update" /tr '"C:\Users\Admin\AppData\Local\Temp\Update.exe"' & exit
  2⤵
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:2112
- - C:\Windows\SysWOW64\schtasks.exe
    schtasks /create /f /sc onlogon /rl highest /tn "Update" /tr '"C:\Users\Admin\AppData\Local\Temp\Update.exe"'
    3⤵
    - System Location Discovery: System Language Discovery
    - Scheduled Task/Job: Scheduled Task
    PID:452
- C:\Windows\SysWOW64\cmd.exe
  C:\Windows\system32\cmd.exe /c ""C:\Users\Admin\AppData\Local\Temp\tmp858B.tmp.bat""
  2⤵
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:1808
- - C:\Windows\SysWOW64\timeout.exe
    timeout 3
    3⤵
    - System Location Discovery: System Language Discovery
    - Delays execution with timeout.exe
    PID:5060
- - C:\Users\Admin\AppData\Local\Temp\Update.exe
    "C:\Users\Admin\AppData\Local\Temp\Update.exe"
    3⤵
    - Executes dropped EXE
    - System Location Discovery: System Language Discovery
    - Suspicious use of AdjustPrivilegeToken
    PID:2380

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\Update.exe

Filesize
45KB

MD5
87b6917db381131a861ba84d4269b0bd

SHA1
801e58b238a02f2d0bb972ee230e77f4bfe4baa1

SHA256
02d242ea2f9251a46c8fc7fdc8a7c00a64491f015b3b8dbe11ff7afaff3fa7c9

SHA512
b297874e06ff77aa8115f9935a7b13fd34a472f904f960708f9c8c86881c6256834362fe8bbdee35914a132d9db4b5fc7f2fb6d418f042cbf5d8a89c5bf5fb6e

Download Submit
C:\Users\Admin\AppData\Local\Temp\tmp858B.tmp.bat

Filesize
153B

MD5
9f78069e17592a06e6ede2e251d2dcf9

SHA1
a2ce78f7dd42b623e0ef4ea0b0f93edb47187cdd

SHA256
aee88ed2672539ebbfa78ec57870409a65081bc6f8c558927ac1da266cd87822

SHA512
e2ad560e9fc04fbef48e18c17cb173583bf1509f7e64d2996114dcddf2941149c776c4e43ee7a92883a094d5331db45f3053eee0b766825efc05f8cfd4bcb8de

Download Submit
memory/2244-0-0x000000007541E000-0x000000007541F000-memory.dmp

Filesize
4KB

Download
memory/2244-1-0x0000000000970000-0x0000000000982000-memory.dmp

Filesize
72KB

Download
memory/2244-2-0x0000000075410000-0x0000000075BC0000-memory.dmp

Filesize
7.7MB

Download
memory/2244-3-0x0000000005300000-0x0000000005366000-memory.dmp

Filesize
408KB

Download
memory/2244-4-0x00000000057A0000-0x000000000583C000-memory.dmp

Filesize
624KB

Download
memory/2244-9-0x0000000075410000-0x0000000075BC0000-memory.dmp

Filesize
7.7MB

Download
memory/2380-14-0x0000000075410000-0x0000000075BC0000-memory.dmp

Filesize
7.7MB

Download
memory/2380-15-0x0000000075410000-0x0000000075BC0000-memory.dmp

Filesize
7.7MB

Download
memory/2380-18-0x0000000005E60000-0x0000000006404000-memory.dmp

Filesize
5.6MB

Download
memory/2380-19-0x00000000066D0000-0x0000000006746000-memory.dmp

Filesize
472KB

Download
memory/2380-20-0x0000000006650000-0x00000000066B8000-memory.dmp

Filesize
416KB

Download
memory/2380-21-0x00000000067A0000-0x00000000067BE000-memory.dmp

Filesize
120KB

Download
memory/2380-22-0x00000000068E0000-0x0000000006972000-memory.dmp

Filesize
584KB

Download
memory/2380-23-0x00000000058F0000-0x0000000005954000-memory.dmp

Filesize
400KB

Download
memory/2380-25-0x0000000075410000-0x0000000075BC0000-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