Malware Analysis Report

2024-08-06 12:59

Sample ID 240605-dx5aqade89
Target cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d
SHA256 cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d
Tags
asyncrat kaskomuz rat
score
10/10

Table of Contents

Analysis Overview

MITRE ATT&CK Matrix

Analysis: static1

Detonation Overview

Signatures

Analysis: behavioral2

Detonation Overview

Command Line

Signatures

Processes

Network

Files

Analysis: behavioral1

Detonation Overview

Command Line

Signatures

Processes

Network

Files

Analysis Overview

score
10/10

SHA256

cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d

Threat Level: Known bad

The file cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d was found to be: Known bad.

Malicious Activity Summary

asyncrat kaskomuz rat

AsyncRat

Detects executables packed with unregistered version of .NET Reactor

Detects executables packed with unregistered version of .NET Reactor

Detects executables attemping to enumerate video devices using WMI

Detects executables containing the string DcRatBy

Detects executables embedding bas64-encoded APIs, command lines, registry keys, etc.

Loads dropped DLL

.NET Reactor proctector

Executes dropped EXE

Suspicious use of SetThreadContext

Enumerates physical storage devices

Unsigned PE

Delays execution with timeout.exe

Suspicious use of AdjustPrivilegeToken

Suspicious use of WriteProcessMemory

Creates scheduled task(s)

Suspicious behavior: EnumeratesProcesses

MITRE ATT&CK Matrix V13

Initial Access
TA0001
Execution
TA0002
Scheduled Task/Job
T1053
Persistence
TA0003
Scheduled Task/Job
T1053
Privilege Escalation
TA0004
Scheduled Task/Job
T1053
Defense Evasion
TA0005
Credential Access
TA0006
Discovery
TA0007
System Information Discovery
T1082
Lateral Movement
TA0008
Collection
TA0009
Exfiltration
TA0010
Command and Control
TA0011
Impact
TA0040
Resource Development
TA0042
Reconnaissance
TA0043

Analysis: static1

Detonation Overview

Reported

2024-06-05 03:24

Signatures

Detects executables packed with unregistered version of .NET Reactor

Description Indicator Process Target
N/A N/A N/A N/A

.NET Reactor proctector

Description Indicator Process Target
N/A N/A N/A N/A

Unsigned PE

Description Indicator Process Target
N/A N/A N/A N/A

Analysis: behavioral2

Detonation Overview

Submitted

2024-06-05 03:24

Reported

2024-06-05 03:28

Platform

win10v2004-20240226-en

Max time kernel

141s

Max time network

161s

Command Line

"C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe"

Signatures

Detects executables packed with unregistered version of .NET Reactor

Description Indicator Process Target
N/A N/A N/A N/A

.NET Reactor proctector

Description Indicator Process Target
N/A N/A N/A N/A

Suspicious use of AdjustPrivilegeToken

Description Indicator Process Target
Token: SeDebugPrivilege N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe N/A

Suspicious use of WriteProcessMemory

Description Indicator Process Target
PID 4156 wrote to memory of 3104 N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe
PID 4156 wrote to memory of 3104 N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe
PID 4156 wrote to memory of 3104 N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe

Processes

C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe

"C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe"

C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe

C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe

C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe

"C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe" --type=utility --utility-sub-type=asset_store.mojom.AssetStoreService --lang=en-US --service-sandbox-type=asset_store_service --no-appcompat-clear --mojo-platform-channel-handle=3808 --field-trial-handle=2264,i,15001568551143786084,90255922961447677,262144 --variations-seed-version /prefetch:8

Network

Country Destination Domain Proto
US 8.8.8.8:53 13.86.106.20.in-addr.arpa udp
US 8.8.8.8:53 203.107.17.2.in-addr.arpa udp
US 8.8.8.8:53 2.159.190.20.in-addr.arpa udp
US 8.8.8.8:53 95.221.229.192.in-addr.arpa udp
US 8.8.8.8:53 217.106.137.52.in-addr.arpa udp
US 13.107.246.64:443 tcp
US 8.8.8.8:53 157.123.68.40.in-addr.arpa udp
US 8.8.8.8:53 171.39.242.20.in-addr.arpa udp
US 8.8.8.8:53 144.107.17.2.in-addr.arpa udp
US 8.8.8.8:53 31.243.111.52.in-addr.arpa udp
US 8.8.8.8:53 240.221.184.93.in-addr.arpa udp
US 8.8.8.8:53 175.117.168.52.in-addr.arpa udp

Files

memory/4156-0-0x000000007529E000-0x000000007529F000-memory.dmp

memory/4156-1-0x0000000000040000-0x000000000016A000-memory.dmp

memory/4156-2-0x0000000075290000-0x0000000075A40000-memory.dmp

memory/4156-3-0x0000000004B80000-0x0000000004C1C000-memory.dmp

memory/4156-4-0x0000000005370000-0x0000000005914000-memory.dmp

memory/4156-5-0x0000000004B70000-0x0000000004B7A000-memory.dmp

memory/4156-8-0x0000000075290000-0x0000000075A40000-memory.dmp

memory/4156-11-0x0000000075290000-0x0000000075A40000-memory.dmp

memory/4156-13-0x0000000075290000-0x0000000075A40000-memory.dmp

Analysis: behavioral1

Detonation Overview

Submitted

2024-06-05 03:24

Reported

2024-06-05 03:28

Platform

win7-20240508-en

Max time kernel

145s

Max time network

148s

Command Line

"C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe"

Signatures

AsyncRat

rat asyncrat

Detects executables attemping to enumerate video devices using WMI

Description Indicator Process Target
N/A N/A N/A N/A
N/A N/A N/A N/A
N/A N/A N/A N/A
N/A N/A N/A N/A
N/A N/A N/A N/A

Detects executables containing the string DcRatBy

Description Indicator Process Target
N/A N/A N/A N/A
N/A N/A N/A N/A
N/A N/A N/A N/A
N/A N/A N/A N/A
N/A N/A N/A N/A

Detects executables embedding bas64-encoded APIs, command lines, registry keys, etc.

Description Indicator Process Target
N/A N/A N/A N/A
N/A N/A N/A N/A
N/A N/A N/A N/A
N/A N/A N/A N/A
N/A N/A N/A N/A

Detects executables packed with unregistered version of .NET Reactor

Description Indicator Process Target
N/A N/A N/A N/A
N/A N/A N/A N/A
N/A N/A N/A N/A

.NET Reactor proctector

Description Indicator Process Target
N/A N/A N/A N/A
N/A N/A N/A N/A
N/A N/A N/A N/A

Executes dropped EXE

Description Indicator Process Target
N/A N/A C:\Users\Admin\AppData\Roaming\Kaskomuz.exe N/A
N/A N/A C:\Users\Admin\AppData\Roaming\Kaskomuz.exe N/A

Loads dropped DLL

Description Indicator Process Target
N/A N/A C:\Windows\SysWOW64\cmd.exe N/A

Suspicious use of SetThreadContext

Description Indicator Process Target
PID 1444 set thread context of 2032 N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe
PID 2624 set thread context of 2576 N/A C:\Users\Admin\AppData\Roaming\Kaskomuz.exe C:\Users\Admin\AppData\Roaming\Kaskomuz.exe

Enumerates physical storage devices

Creates scheduled task(s)

persistence
Description Indicator Process Target
N/A N/A C:\Windows\SysWOW64\schtasks.exe N/A

Delays execution with timeout.exe

evasion
Description Indicator Process Target
N/A N/A C:\Windows\SysWOW64\timeout.exe N/A

Suspicious behavior: EnumeratesProcesses

Description Indicator Process Target
N/A N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe N/A
N/A N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe N/A

Suspicious use of AdjustPrivilegeToken

Description Indicator Process Target
Token: SeDebugPrivilege N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe N/A
Token: SeDebugPrivilege N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe N/A
Token: SeDebugPrivilege N/A C:\Users\Admin\AppData\Roaming\Kaskomuz.exe N/A
Token: SeDebugPrivilege N/A C:\Users\Admin\AppData\Roaming\Kaskomuz.exe N/A

Suspicious use of WriteProcessMemory

Description Indicator Process Target
PID 1444 wrote to memory of 2032 N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe
PID 1444 wrote to memory of 2032 N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe
PID 1444 wrote to memory of 2032 N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe
PID 1444 wrote to memory of 2032 N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe
PID 1444 wrote to memory of 2032 N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe
PID 1444 wrote to memory of 2032 N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe
PID 2032 wrote to memory of 2720 N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe C:\Windows\SysWOW64\cmd.exe
PID 2032 wrote to memory of 2720 N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe C:\Windows\SysWOW64\cmd.exe
PID 2032 wrote to memory of 2720 N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe C:\Windows\SysWOW64\cmd.exe
PID 2032 wrote to memory of 2720 N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe C:\Windows\SysWOW64\cmd.exe
PID 2032 wrote to memory of 2520 N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe C:\Windows\SysWOW64\cmd.exe
PID 2032 wrote to memory of 2520 N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe C:\Windows\SysWOW64\cmd.exe
PID 2032 wrote to memory of 2520 N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe C:\Windows\SysWOW64\cmd.exe
PID 2032 wrote to memory of 2520 N/A C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe C:\Windows\SysWOW64\cmd.exe
PID 2720 wrote to memory of 2016 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\schtasks.exe
PID 2720 wrote to memory of 2016 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\schtasks.exe
PID 2720 wrote to memory of 2016 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\schtasks.exe
PID 2720 wrote to memory of 2016 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\schtasks.exe
PID 2520 wrote to memory of 2796 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\timeout.exe
PID 2520 wrote to memory of 2796 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\timeout.exe
PID 2520 wrote to memory of 2796 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\timeout.exe
PID 2520 wrote to memory of 2796 N/A C:\Windows\SysWOW64\cmd.exe C:\Windows\SysWOW64\timeout.exe
PID 2520 wrote to memory of 2624 N/A C:\Windows\SysWOW64\cmd.exe C:\Users\Admin\AppData\Roaming\Kaskomuz.exe
PID 2520 wrote to memory of 2624 N/A C:\Windows\SysWOW64\cmd.exe C:\Users\Admin\AppData\Roaming\Kaskomuz.exe
PID 2520 wrote to memory of 2624 N/A C:\Windows\SysWOW64\cmd.exe C:\Users\Admin\AppData\Roaming\Kaskomuz.exe
PID 2520 wrote to memory of 2624 N/A C:\Windows\SysWOW64\cmd.exe C:\Users\Admin\AppData\Roaming\Kaskomuz.exe
PID 2624 wrote to memory of 2576 N/A C:\Users\Admin\AppData\Roaming\Kaskomuz.exe C:\Users\Admin\AppData\Roaming\Kaskomuz.exe
PID 2624 wrote to memory of 2576 N/A C:\Users\Admin\AppData\Roaming\Kaskomuz.exe C:\Users\Admin\AppData\Roaming\Kaskomuz.exe
PID 2624 wrote to memory of 2576 N/A C:\Users\Admin\AppData\Roaming\Kaskomuz.exe C:\Users\Admin\AppData\Roaming\Kaskomuz.exe
PID 2624 wrote to memory of 2576 N/A C:\Users\Admin\AppData\Roaming\Kaskomuz.exe C:\Users\Admin\AppData\Roaming\Kaskomuz.exe
PID 2624 wrote to memory of 2576 N/A C:\Users\Admin\AppData\Roaming\Kaskomuz.exe C:\Users\Admin\AppData\Roaming\Kaskomuz.exe
PID 2624 wrote to memory of 2576 N/A C:\Users\Admin\AppData\Roaming\Kaskomuz.exe C:\Users\Admin\AppData\Roaming\Kaskomuz.exe

Processes

C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe

"C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe"

C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe

C:\Users\Admin\AppData\Local\Temp\cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d.exe

C:\Windows\SysWOW64\cmd.exe

"C:\Windows\System32\cmd.exe" /c schtasks /create /f /sc onlogon /rl highest /tn "Kaskomuz" /tr '"C:\Users\Admin\AppData\Roaming\Kaskomuz.exe"' & exit

C:\Windows\SysWOW64\cmd.exe

cmd /c ""C:\Users\Admin\AppData\Local\Temp\tmp2B64.tmp.bat""

C:\Windows\SysWOW64\schtasks.exe

schtasks /create /f /sc onlogon /rl highest /tn "Kaskomuz" /tr '"C:\Users\Admin\AppData\Roaming\Kaskomuz.exe"'

C:\Windows\SysWOW64\timeout.exe

timeout 3

C:\Users\Admin\AppData\Roaming\Kaskomuz.exe

"C:\Users\Admin\AppData\Roaming\Kaskomuz.exe"

C:\Users\Admin\AppData\Roaming\Kaskomuz.exe

C:\Users\Admin\AppData\Roaming\Kaskomuz.exe

Network

Country Destination Domain Proto
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp
BG 80.76.49.154:8848 tcp

Files

memory/1444-0-0x00000000747AE000-0x00000000747AF000-memory.dmp

memory/1444-1-0x0000000000AA0000-0x0000000000BCA000-memory.dmp

memory/1444-2-0x00000000747A0000-0x0000000074E8E000-memory.dmp

memory/1444-3-0x00000000004B0000-0x00000000004BA000-memory.dmp

memory/2032-21-0x0000000000400000-0x0000000000422000-memory.dmp

memory/2032-18-0x0000000000400000-0x0000000000422000-memory.dmp

memory/2032-15-0x0000000000400000-0x0000000000422000-memory.dmp

memory/1444-22-0x00000000747A0000-0x0000000074E8E000-memory.dmp

memory/1444-23-0x00000000747A0000-0x0000000074E8E000-memory.dmp

memory/2032-24-0x00000000747A0000-0x0000000074E8E000-memory.dmp

memory/2032-25-0x00000000747A0000-0x0000000074E8E000-memory.dmp

C:\Users\Admin\AppData\Local\Temp\tmp2B64.tmp.bat

MD5 60af3d9364e757f2b7aea0b88c000cb6
SHA1 136ba0caaf9fb28bfcb5a552ea77730f549c41f3
SHA256 2918e7b6f4ec053808150e34da1a4f89006e8321df22cf795f0b1982be401dd1
SHA512 c32586fe97a06ffbd947e1fe8705d2ebb2bf99b758b68f9ab929d44fdd3eb20ee6da88077f58245bbb659974fd882e6e7a3f7fbd92a7c4e9c5adf2e081f9bd5f

memory/2032-35-0x00000000747A0000-0x0000000074E8E000-memory.dmp

\Users\Admin\AppData\Roaming\Kaskomuz.exe

MD5 2f3c519c599dc02d11bf57918b798ee3
SHA1 82ad01ac3e2cdb9d795cf6d7ab2ae3d3a417843a
SHA256 cae5d1df4e948b813a01bb83d087b6438d91a1aeb3f6a0a16a328373edfe851d
SHA512 c2d6016c9bae5d5bf41583a5f2de54f8e8a0effd6a3af97a6259ab73b23a505e15f0c96df6b82dbba40d3b9562ebb5a5e42961088b123433bede257e6c4e8f06

memory/2624-39-0x0000000000CE0000-0x0000000000E0A000-memory.dmp

memory/2576-54-0x0000000000400000-0x0000000000422000-memory.dmp

memory/2576-56-0x0000000000400000-0x0000000000422000-memory.dmp