asyncrat | fce223eb8d3e1ae81cd4d54f4f74a1a551c42dedd5c8d56554a4a23ade81db3d

General

Target
tmpyzk0c4vx.exe
Size 45KB
Sample260522-x6zw5sf14v
SHA256 fce223eb8d3e1ae81cd4d54f4f74a1a551c42dedd5c8d56554a4a23ade81db3d
MD5 fc5cc90eab47778ddd2ca3eda7f361fe
SHA1 970a9cb0de88205194095259e89ca0f22e6a852e
SHA512 4fd53071ee7ea6218d0f71d77bf07540fc57863a64bbda33530eea47b16768e3e1675392a1b2995a20feefae870ce60e669471fa2e4f6c4292cf60d87faec6e9
SSDEEP 768:wuD/ZTpw7bmaWUg3gSk0mo2qlneeXK5oibbb6TN8/nPI6WzjbtgX3izq4Acvl+pu:wuD/ZTpMZSB2DeEqTNKA6W3b6XSzhZvv
TLSH
T1EB231A103BE8C12BF2BE4F74A9F26145867AF2772603D94E1CC4519B5623FC6CA426ED
MD5 SHA1 SHA512 SSDEEP TLSH

Score

10^/10

default defense_evasion discovery execution asyncrat persistence rat

Malware Config

Extracted

Family

asyncrat

Version

0.5.8

Botnet

Default

C2

sfrecess.com:443
sfrecess.com:80
sfrecess.com:7797
sfrecess.com:8707
sfrecess.com:6620
www.sfrecess.com:443
www.sfrecess.com:80
www.sfrecess.com:7797
www.sfrecess.com:8707
www.sfrecess.com:6620
remote.sfrecess.com:443
remote.sfrecess.com:80
remote.sfrecess.com:7797
remote.sfrecess.com:8707
remote.sfrecess.com:6620
sasser.sfrecess.com:443
sasser.sfrecess.com:80
sasser.sfrecess.com:7797
sasser.sfrecess.com:8707
sasser.sfrecess.com:6620
iloveyou.sfrecess.com:443
iloveyou.sfrecess.com:80
iloveyou.sfrecess.com:7797
iloveyou.sfrecess.com:8707
iloveyou.sfrecess.com:6620
malware.sfrecess.com:443
malware.sfrecess.com:80
malware.sfrecess.com:7797
malware.sfrecess.com:8707
malware.sfrecess.com:6620

Mutex

3E5LMhaZAwK3

Attributes

delay
0
install
true
install_file
mf18w.exe
install_folder
%AppData%

aes.plain

Signatures

Family: 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
behavioral1/files/0x0030000000027a6e-8.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-1-5-21-4045429996-2364296335-1634900306-1000\Control Panel\International\Geo\Nation	tmpyzk0c4vx.exe

Executes dropped EXE 2 IoCs

pid	Process
1212	mf18w.exe
5892	mf18w.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 7 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	schtasks.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	mf18w.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	mf18w.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	tmpyzk0c4vx.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	cmd.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	cmd.exe

Delays execution with timeout.exe 1 IoCs

defense_evasion

pid	Process
2008	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
1124	schtasks.exe

Suspicious behavior: EnumeratesProcesses 21 IoCs

pid	Process
4756	tmpyzk0c4vx.exe
4756	tmpyzk0c4vx.exe
4756	tmpyzk0c4vx.exe
4756	tmpyzk0c4vx.exe
4756	tmpyzk0c4vx.exe
4756	tmpyzk0c4vx.exe
4756	tmpyzk0c4vx.exe
4756	tmpyzk0c4vx.exe
4756	tmpyzk0c4vx.exe
4756	tmpyzk0c4vx.exe
4756	tmpyzk0c4vx.exe
4756	tmpyzk0c4vx.exe
4756	tmpyzk0c4vx.exe
4756	tmpyzk0c4vx.exe
4756	tmpyzk0c4vx.exe
4756	tmpyzk0c4vx.exe
4756	tmpyzk0c4vx.exe
4756	tmpyzk0c4vx.exe
4756	tmpyzk0c4vx.exe
4756	tmpyzk0c4vx.exe
4756	tmpyzk0c4vx.exe

Suspicious use of AdjustPrivilegeToken 2 IoCs

description	pid	Process
Token: SeDebugPrivilege	4756	tmpyzk0c4vx.exe
Token: SeDebugPrivilege	1212	mf18w.exe

Suspicious use of WriteProcessMemory 5 IoCs

description	pid	Process	procid_target
PID 4756 wrote to memory of 3676	4756	tmpyzk0c4vx.exe	82
PID 4756 wrote to memory of 2076	4756	tmpyzk0c4vx.exe	84
PID 2076 wrote to memory of 2008	2076	cmd.exe	86
PID 3676 wrote to memory of 1124	3676	cmd.exe	87
PID 2076 wrote to memory of 5892	2076	cmd.exe	90

C:\Users\Admin\AppData\Local\Temp\tmpyzk0c4vx.exe
"C:\Users\Admin\AppData\Local\Temp\tmpyzk0c4vx.exe"
1⤵
- Checks computer location settings
- System Location Discovery: System Language Discovery
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:4756
- C:\Windows\SysWOW64\cmd.exe
  "C:\Windows\System32\cmd.exe" /c schtasks /create /f /sc onlogon /rl highest /tn "mf18w" /tr '"C:\Users\Admin\AppData\Roaming\mf18w.exe"' & exit
  2⤵
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:3676
- - C:\Windows\SysWOW64\schtasks.exe
    schtasks /create /f /sc onlogon /rl highest /tn "mf18w" /tr '"C:\Users\Admin\AppData\Roaming\mf18w.exe"'
    3⤵
    - System Location Discovery: System Language Discovery
    - Scheduled Task/Job: Scheduled Task
    PID:1124
- C:\Windows\SysWOW64\cmd.exe
  C:\Windows\system32\cmd.exe /c ""C:\Users\Admin\AppData\Local\Temp\tmpF4D.tmp.bat""
  2⤵
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:2076
- - C:\Windows\SysWOW64\timeout.exe
    timeout 3
    3⤵
    - System Location Discovery: System Language Discovery
    - Delays execution with timeout.exe
    PID:2008
- - C:\Users\Admin\AppData\Roaming\mf18w.exe
    "C:\Users\Admin\AppData\Roaming\mf18w.exe"
    3⤵
    - Executes dropped EXE
    - System Location Discovery: System Language Discovery
    PID:5892

C:\Users\Admin\AppData\Roaming\mf18w.exe
"C:\Users\Admin\AppData\Roaming\mf18w.exe"
1⤵
- Executes dropped EXE
- System Location Discovery: System Language Discovery
- Suspicious use of AdjustPrivilegeToken
PID:1212

Network

MITRE ATT&CK Enterprise v16

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

tmpF4D.tmp.bat

Path C:\Users\Admin\AppData\Local\Temp\tmpF4D.tmp.bat
Size 148B
SHA256 ef228aa92726ed2f161f13da3b15f1be3bac8ae938aea6b2e1f53b9bb2e6e3ef
MD5 6f00d2692d1de180d91891b57aca5cb6
SHA1 dcffe6c03cd5bcd8536335375dc1bf95f4216ebf
SHA512 cc8b4bab8ae07eabaee609af9be96a736c841ee3b9d20d2ffc27b5eaad794760ecb5ced69386f1918263b35ef9853d0ca84ea85157df316a8b5293a1fab57e29
TLSH
T1F0C02B4361C6FACE2806146312FED4CD9172AD593F80FB00C304440D26C0448F8D9381
MD5 SHA1 SHA512 TLSH

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mf18w.exe

Path C:\Users\Admin\AppData\Roaming\mf18w.exe
Size 45KB
SHA256 fce223eb8d3e1ae81cd4d54f4f74a1a551c42dedd5c8d56554a4a23ade81db3d
MD5 fc5cc90eab47778ddd2ca3eda7f361fe
SHA1 970a9cb0de88205194095259e89ca0f22e6a852e
SHA512 4fd53071ee7ea6218d0f71d77bf07540fc57863a64bbda33530eea47b16768e3e1675392a1b2995a20feefae870ce60e669471fa2e4f6c4292cf60d87faec6e9
SSDEEP 768:wuD/ZTpw7bmaWUg3gSk0mo2qlneeXK5oibbb6TN8/nPI6WzjbtgX3izq4Acvl+pu:wuD/ZTpMZSB2DeEqTNKA6W3b6XSzhZvv
TLSH
T1EB231A103BE8C12BF2BE4F74A9F26145867AF2772603D94E1CC4519B5623FC6CA426ED
MD5 SHA1 SHA512 SSDEEP TLSH

Submit Download

memory/4756-0-0x0000000000AA0000-0x0000000000AB2000-memory.dmp

Download

memory/4756-1-0x0000000005540000-0x0000000005550000-memory.dmp

Download

memory/4756-2-0x0000000005450000-0x00000000054EC000-memory.dmp

Download

Analysis

Sharing

General

Malware Config

Extracted

Signatures

Processes

Network

MITRE ATT&CK Enterprise v16

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