asyncrat | 5e1b238642a824af1333443f125f3e0e699768c9a33be81f899f65fecd4ba86f

General

Target

Client.exe
Size

74KB
MD5

8858177a6b8c6874dc44570c1d6e47ab
SHA1

e5692c7e3198378ef684dc4482599610bc8d1e60
SHA256

5e1b238642a824af1333443f125f3e0e699768c9a33be81f899f65fecd4ba86f
SHA512

92bfaf9d624c5c05cafff01fa9d21467e99f6f46455f2441e500e3f0f539be12b96968e1c7b96f9cca73141e1326476be58e9b3e7c0d2256685dc2ad55519876
SSDEEP

1536:qUsgcxbVzCt+PPMVme9VdQuDI6H1bf/264QzcWLVclN:qU5cxblTPPMVme9VdQsH1bfO64QvBY

Score

10^/10

asyncrat default discovery rat

Malware Config

Extracted

Family

asyncrat

Version

L838 RAT v1.0.0

Botnet

Default

Mutex

uhuhlilars

Attributes

delay
3
install
true
install_file
Windows Font Manager.exe
install_folder
%AppData%
pastebin_config
https://pastebin.com/raw/rVJQPNVe

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
behavioral1/files/0x000d000000024159-13.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-1-5-21-446031748-3036493239-2009529691-1000\Control Panel\International\Geo\Nation	Client.exe

Executes dropped EXE 1 IoCs

pid	Process
2500	Windows Font Manager.exe

Checks installed software on the system 1 TTPs
Looks up Uninstall key entries in the registry to enumerate software on the system.
discovery

Query Registry
T1012

Legitimate hosting services abused for malware hosting/C2 1 TTPs 2 IoCs

Web Service

T1102

flow	ioc
29	pastebin.com
30	pastebin.com

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

System Information Discovery
T1082

Delays execution with timeout.exe 1 IoCs

defense_evasion

pid	Process
3000	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
4360	schtasks.exe

Suspicious behavior: EnumeratesProcesses 26 IoCs

pid	Process
5092	Client.exe
5092	Client.exe
5092	Client.exe
5092	Client.exe
5092	Client.exe
5092	Client.exe
5092	Client.exe
5092	Client.exe
5092	Client.exe
5092	Client.exe
5092	Client.exe
5092	Client.exe
5092	Client.exe
5092	Client.exe
5092	Client.exe
5092	Client.exe
5092	Client.exe
5092	Client.exe
5092	Client.exe
5092	Client.exe
5092	Client.exe
5092	Client.exe
5092	Client.exe
2500	Windows Font Manager.exe
2500	Windows Font Manager.exe
2500	Windows Font Manager.exe

Suspicious use of AdjustPrivilegeToken 2 IoCs

description	pid	Process
Token: SeDebugPrivilege	5092	Client.exe
Token: SeDebugPrivilege	2500	Windows Font Manager.exe

Suspicious use of SetWindowsHookEx 1 IoCs

pid	Process
2500	Windows Font Manager.exe

Suspicious use of WriteProcessMemory 10 IoCs

description	pid	Process	procid_target
PID 5092 wrote to memory of 4776	5092	Client.exe	95
PID 5092 wrote to memory of 4776	5092	Client.exe	95
PID 5092 wrote to memory of 2148	5092	Client.exe	96
PID 5092 wrote to memory of 2148	5092	Client.exe	96
PID 2148 wrote to memory of 3000	2148	cmd.exe	99
PID 2148 wrote to memory of 3000	2148	cmd.exe	99
PID 4776 wrote to memory of 4360	4776	cmd.exe	100
PID 4776 wrote to memory of 4360	4776	cmd.exe	100
PID 2148 wrote to memory of 2500	2148	cmd.exe	102
PID 2148 wrote to memory of 2500	2148	cmd.exe	102

Uses Task Scheduler COM API 1 TTPs
The Task Scheduler COM API can be used to schedule applications to run on boot or at set times.
persistence

Query Registry
T1012

C:\Users\Admin\AppData\Local\Temp\Client.exe
"C:\Users\Admin\AppData\Local\Temp\Client.exe"
1⤵
- Checks computer location settings
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:5092
- C:\Windows\System32\cmd.exe
  "C:\Windows\System32\cmd.exe" /c schtasks /create /f /sc onlogon /rl highest /tn "Windows Font Manager" /tr '"C:\Users\Admin\AppData\Roaming\Windows Font Manager.exe"' & exit
  2⤵
  - Suspicious use of WriteProcessMemory
  PID:4776
- - C:\Windows\system32\schtasks.exe
    schtasks /create /f /sc onlogon /rl highest /tn "Windows Font Manager" /tr '"C:\Users\Admin\AppData\Roaming\Windows Font Manager.exe"'
    3⤵
    - Scheduled Task/Job: Scheduled Task
    PID:4360
- C:\Windows\system32\cmd.exe
  C:\Windows\system32\cmd.exe /c ""C:\Users\Admin\AppData\Local\Temp\tmp87ED.tmp.bat""
  2⤵
  - Suspicious use of WriteProcessMemory
  PID:2148
- - C:\Windows\system32\timeout.exe
    timeout 3
    3⤵
    - Delays execution with timeout.exe
    PID:3000
- - C:\Users\Admin\AppData\Roaming\Windows Font Manager.exe
    "C:\Users\Admin\AppData\Roaming\Windows Font Manager.exe"
    3⤵
    - Executes dropped EXE
    - Suspicious behavior: EnumeratesProcesses
    - Suspicious use of AdjustPrivilegeToken
    - Suspicious use of SetWindowsHookEx
    PID:2500

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

3

T1012

System Information Discovery

2

T1082

Lateral Movement

Collection

Command and Control

Web Service

1

T1102

Exfiltration

Impact

Replay Monitor

Loading Replay Monitor...

Downloads

C:\Users\Admin\AppData\Local\Temp\tmp87ED.tmp.bat

Filesize
164B

MD5
1fa3a4a5fa15185b1096134e8e7ae925

SHA1
6655c9f5dd27b65740bad9c822cc21666fc234a1

SHA256
0a433fbc4db158452e0f3a4cc90f58456be07776f17d430fc16c49cf5d6a3070

SHA512
ceab5ccbc5c10fae98b6d0dc9d57f1c2ba1a60d9f843f1cd17f5fd09ab3f5dec74f610faa68842a64dc1f10223893c0a3546351aa27e80c6ed77b095f4dc60f2

Download Submit
C:\Users\Admin\AppData\Roaming\MyData\DataLogs.conf

Filesize
8B

MD5
cf759e4c5f14fe3eec41b87ed756cea8

SHA1
c27c796bb3c2fac929359563676f4ba1ffada1f5

SHA256
c9f9f193409217f73cc976ad078c6f8bf65d3aabcf5fad3e5a47536d47aa6761

SHA512
c7f832aee13a5eb36d145f35d4464374a9e12fa2017f3c2257442d67483b35a55eccae7f7729243350125b37033e075efbc2303839fd86b81b9b4dca3626953b

Download Submit
C:\Users\Admin\AppData\Roaming\Windows Font Manager.exe

Filesize
74KB

MD5
8858177a6b8c6874dc44570c1d6e47ab

SHA1
e5692c7e3198378ef684dc4482599610bc8d1e60

SHA256
5e1b238642a824af1333443f125f3e0e699768c9a33be81f899f65fecd4ba86f

SHA512
92bfaf9d624c5c05cafff01fa9d21467e99f6f46455f2441e500e3f0f539be12b96968e1c7b96f9cca73141e1326476be58e9b3e7c0d2256685dc2ad55519876

Download Submit
memory/2500-17-0x000000001D190000-0x000000001D206000-memory.dmp

Filesize
472KB

Download
memory/2500-18-0x0000000003190000-0x00000000031A0000-memory.dmp

Filesize
64KB

Download
memory/2500-19-0x0000000003250000-0x000000000326E000-memory.dmp

Filesize
120KB

Download
memory/5092-0-0x00007FF8E2B33000-0x00007FF8E2B35000-memory.dmp

Filesize
8KB

Download
memory/5092-1-0x0000000000420000-0x0000000000438000-memory.dmp

Filesize
96KB

Download
memory/5092-3-0x00007FF8E2B30000-0x00007FF8E35F1000-memory.dmp

Filesize
10.8MB

Download
memory/5092-8-0x00007FF8E2B30000-0x00007FF8E35F1000-memory.dmp

Filesize
10.8MB

Download
memory/5092-9-0x00007FF8E2B30000-0x00007FF8E35F1000-memory.dmp

Filesize
10.8MB

Download

Analysis

Sharing

General

Malware Config

Extracted

Signatures

Processes

Network

MITRE ATT&CK Enterprise v15

Replay Monitor

Loading Replay Monitor...

Downloads