Analysis Overview
SHA256
f2e04196e1353ad216e077e0aeb2e1ab8ee93b8b16b205422b4cc6d8adc50cc2
Threat Level: Known bad
The file Client-built.exe was found to be: Known bad.
Malicious Activity Summary
Quasar RAT
Quasar family
Quasar payload
Executes dropped EXE
Unsigned PE
Uses Task Scheduler COM API
Suspicious use of SetWindowsHookEx
Suspicious use of WriteProcessMemory
Creates scheduled task(s)
Suspicious use of AdjustPrivilegeToken
MITRE ATT&CK
Enterprise Matrix V15
Analysis: static1
Detonation Overview
Reported
2024-03-31 00:43
Signatures
Quasar family
Quasar payload
| 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: behavioral1
Detonation Overview
Submitted
2024-03-31 00:43
Reported
2024-03-31 01:14
Platform
win10-20240221-en
Max time kernel
1788s
Max time network
1793s
Command Line
Signatures
Quasar RAT
Quasar payload
| Description | Indicator | Process | Target |
| 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\Windows\WOS64UPD.exe | N/A |
Creates scheduled task(s)
| Description | Indicator | Process | Target |
| N/A | N/A | C:\Windows\SYSTEM32\schtasks.exe | N/A |
| N/A | N/A | C:\Windows\SYSTEM32\schtasks.exe | N/A |
Suspicious use of AdjustPrivilegeToken
| Description | Indicator | Process | Target |
| Token: SeDebugPrivilege | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | N/A |
| Token: SeDebugPrivilege | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | N/A |
Suspicious use of SetWindowsHookEx
| Description | Indicator | Process | Target |
| N/A | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | N/A |
Suspicious use of WriteProcessMemory
| Description | Indicator | Process | Target |
| PID 2516 wrote to memory of 4416 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 2516 wrote to memory of 4416 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 2516 wrote to memory of 4508 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 2516 wrote to memory of 4508 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 4508 wrote to memory of 4104 | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 4508 wrote to memory of 4104 | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | C:\Windows\SYSTEM32\schtasks.exe |
Uses Task Scheduler COM API
Processes
C:\Users\Admin\AppData\Local\Temp\Client-built.exe
"C:\Users\Admin\AppData\Local\Temp\Client-built.exe"
C:\Windows\SYSTEM32\schtasks.exe
"schtasks" /create /tn "Windows Updater" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe" /rl HIGHEST /f
C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe
"C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe"
C:\Windows\SYSTEM32\schtasks.exe
"schtasks" /create /tn "Windows Updater" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe" /rl HIGHEST /f
Network
| Country | Destination | Domain | Proto |
| GB | 140.238.91.110:44867 | tcp | |
| US | 8.8.8.8:53 | ipwho.is | udp |
| DE | 195.201.57.90:443 | ipwho.is | tcp |
| US | 8.8.8.8:53 | 110.91.238.140.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 240.221.184.93.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 90.57.201.195.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 19.229.111.52.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 25.73.42.20.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 40.134.221.88.in-addr.arpa | udp |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp |
Files
memory/2516-0-0x00000000007B0000-0x0000000000AD4000-memory.dmp
memory/2516-1-0x00007FF850B40000-0x00007FF85152C000-memory.dmp
memory/2516-2-0x000000001B8C0000-0x000000001B8D0000-memory.dmp
C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe
| MD5 | 57045c2bf3377b12aa5abce21cc0a99d |
| SHA1 | 217202ed404f25fc550ad70fd7066b0fe8773ef9 |
| SHA256 | f2e04196e1353ad216e077e0aeb2e1ab8ee93b8b16b205422b4cc6d8adc50cc2 |
| SHA512 | 9ab46cc194eeaabb75777457a01328f5a8d2ebf604efba0623575cf25c04e206e416ee72db17e3c92a9d363330f82fa3ce2aac64c2a4a61d4dce34d79b73366e |
memory/4508-8-0x00007FF850B40000-0x00007FF85152C000-memory.dmp
memory/2516-9-0x00007FF850B40000-0x00007FF85152C000-memory.dmp
memory/4508-10-0x00000000029D0000-0x00000000029E0000-memory.dmp
memory/4508-11-0x000000001C020000-0x000000001C070000-memory.dmp
memory/4508-12-0x000000001C130000-0x000000001C1E2000-memory.dmp
memory/4508-15-0x000000001BFF0000-0x000000001C002000-memory.dmp
memory/4508-16-0x000000001C0F0000-0x000000001C12E000-memory.dmp
memory/4508-17-0x00007FF850B40000-0x00007FF85152C000-memory.dmp
memory/4508-18-0x00000000029D0000-0x00000000029E0000-memory.dmp
Analysis: behavioral2
Detonation Overview
Submitted
2024-03-31 00:43
Reported
2024-03-31 01:14
Platform
win10v2004-20240226-en
Max time kernel
1772s
Max time network
1805s
Command Line
Signatures
Quasar RAT
Quasar payload
| Description | Indicator | Process | Target |
| 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\Windows\WOS64UPD.exe | N/A |
Creates scheduled task(s)
| Description | Indicator | Process | Target |
| N/A | N/A | C:\Windows\SYSTEM32\schtasks.exe | N/A |
| N/A | N/A | C:\Windows\SYSTEM32\schtasks.exe | N/A |
Suspicious use of AdjustPrivilegeToken
| Description | Indicator | Process | Target |
| Token: SeDebugPrivilege | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | N/A |
| Token: SeDebugPrivilege | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | N/A |
Suspicious use of SetWindowsHookEx
| Description | Indicator | Process | Target |
| N/A | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | N/A |
Suspicious use of WriteProcessMemory
| Description | Indicator | Process | Target |
| PID 3516 wrote to memory of 4872 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 3516 wrote to memory of 4872 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 3516 wrote to memory of 3192 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 3516 wrote to memory of 3192 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 3192 wrote to memory of 4248 | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 3192 wrote to memory of 4248 | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | C:\Windows\SYSTEM32\schtasks.exe |
Uses Task Scheduler COM API
Processes
C:\Users\Admin\AppData\Local\Temp\Client-built.exe
"C:\Users\Admin\AppData\Local\Temp\Client-built.exe"
C:\Windows\SYSTEM32\schtasks.exe
"schtasks" /create /tn "Windows Updater" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe" /rl HIGHEST /f
C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe
"C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe"
C:\Windows\SYSTEM32\schtasks.exe
"schtasks" /create /tn "Windows Updater" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe" /rl HIGHEST /f
Network
| Country | Destination | Domain | Proto |
| US | 8.8.8.8:53 | 71.31.126.40.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 40.134.221.88.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 97.17.167.52.in-addr.arpa | udp |
| GB | 140.238.91.110:44867 | tcp | |
| US | 8.8.8.8:53 | ipwho.is | udp |
| DE | 195.201.57.90:443 | ipwho.is | tcp |
| US | 8.8.8.8:53 | 110.91.238.140.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 90.57.201.195.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 209.205.72.20.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 157.123.68.40.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 15.164.165.52.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 18.134.221.88.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 240.221.184.93.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 12.173.189.20.in-addr.arpa | udp |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp |
Files
memory/3516-0-0x00000000000B0000-0x00000000003D4000-memory.dmp
memory/3516-1-0x00007FFD456C0000-0x00007FFD46181000-memory.dmp
memory/3516-2-0x000000001B0E0000-0x000000001B0F0000-memory.dmp
C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe
| MD5 | 57045c2bf3377b12aa5abce21cc0a99d |
| SHA1 | 217202ed404f25fc550ad70fd7066b0fe8773ef9 |
| SHA256 | f2e04196e1353ad216e077e0aeb2e1ab8ee93b8b16b205422b4cc6d8adc50cc2 |
| SHA512 | 9ab46cc194eeaabb75777457a01328f5a8d2ebf604efba0623575cf25c04e206e416ee72db17e3c92a9d363330f82fa3ce2aac64c2a4a61d4dce34d79b73366e |
memory/3516-8-0x00007FFD456C0000-0x00007FFD46181000-memory.dmp
memory/3192-9-0x00007FFD456C0000-0x00007FFD46181000-memory.dmp
memory/3192-10-0x000000001B860000-0x000000001B870000-memory.dmp
memory/3192-11-0x000000001B7A0000-0x000000001B7F0000-memory.dmp
memory/3192-12-0x000000001C420000-0x000000001C4D2000-memory.dmp
memory/3192-15-0x000000001C360000-0x000000001C372000-memory.dmp
memory/3192-16-0x000000001C3C0000-0x000000001C3FC000-memory.dmp
memory/3192-17-0x00007FFD456C0000-0x00007FFD46181000-memory.dmp
memory/3192-18-0x000000001B860000-0x000000001B870000-memory.dmp
Analysis: behavioral3
Detonation Overview
Submitted
2024-03-31 00:43
Reported
2024-03-31 01:22
Platform
win11-20240221-en
Max time kernel
1724s
Max time network
1776s
Command Line
Signatures
Quasar RAT
Quasar payload
| Description | Indicator | Process | Target |
| 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\Windows\WOS64UPD.exe | N/A |
Creates scheduled task(s)
| Description | Indicator | Process | Target |
| N/A | N/A | C:\Windows\SYSTEM32\schtasks.exe | N/A |
| N/A | N/A | C:\Windows\SYSTEM32\schtasks.exe | N/A |
Suspicious use of AdjustPrivilegeToken
| Description | Indicator | Process | Target |
| Token: SeDebugPrivilege | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | N/A |
| Token: SeDebugPrivilege | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | N/A |
Suspicious use of SetWindowsHookEx
| Description | Indicator | Process | Target |
| N/A | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | N/A |
Suspicious use of WriteProcessMemory
| Description | Indicator | Process | Target |
| PID 3612 wrote to memory of 4000 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 3612 wrote to memory of 4000 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 3612 wrote to memory of 1676 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 3612 wrote to memory of 1676 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 1676 wrote to memory of 4380 | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 1676 wrote to memory of 4380 | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | C:\Windows\SYSTEM32\schtasks.exe |
Uses Task Scheduler COM API
Processes
C:\Users\Admin\AppData\Local\Temp\Client-built.exe
"C:\Users\Admin\AppData\Local\Temp\Client-built.exe"
C:\Windows\SYSTEM32\schtasks.exe
"schtasks" /create /tn "Windows Updater" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe" /rl HIGHEST /f
C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe
"C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe"
C:\Windows\SYSTEM32\schtasks.exe
"schtasks" /create /tn "Windows Updater" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe" /rl HIGHEST /f
Network
| Country | Destination | Domain | Proto |
| GB | 140.238.91.110:44867 | tcp | |
| DE | 195.201.57.90:443 | ipwho.is | tcp |
| US | 8.8.8.8:53 | 8.8.8.8.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 240.221.184.93.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 90.57.201.195.in-addr.arpa | udp |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp | |
| GB | 140.238.91.110:44867 | tcp |
Files
memory/3612-0-0x00000000001A0000-0x00000000004C4000-memory.dmp
memory/3612-1-0x00007FFEA6C80000-0x00007FFEA7742000-memory.dmp
memory/3612-2-0x000000001B210000-0x000000001B220000-memory.dmp
C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe
| MD5 | 57045c2bf3377b12aa5abce21cc0a99d |
| SHA1 | 217202ed404f25fc550ad70fd7066b0fe8773ef9 |
| SHA256 | f2e04196e1353ad216e077e0aeb2e1ab8ee93b8b16b205422b4cc6d8adc50cc2 |
| SHA512 | 9ab46cc194eeaabb75777457a01328f5a8d2ebf604efba0623575cf25c04e206e416ee72db17e3c92a9d363330f82fa3ce2aac64c2a4a61d4dce34d79b73366e |
memory/3612-8-0x00007FFEA6C80000-0x00007FFEA7742000-memory.dmp
memory/1676-9-0x00007FFEA6C80000-0x00007FFEA7742000-memory.dmp
memory/1676-10-0x00000000018C0000-0x00000000018D0000-memory.dmp
memory/1676-11-0x000000001C4A0000-0x000000001C4F0000-memory.dmp
memory/1676-12-0x000000001C5B0000-0x000000001C662000-memory.dmp
memory/1676-15-0x000000001C540000-0x000000001C552000-memory.dmp
memory/1676-16-0x000000001D1C0000-0x000000001D1FC000-memory.dmp
memory/1676-17-0x00007FFEA6C80000-0x00007FFEA7742000-memory.dmp
memory/1676-18-0x00000000018C0000-0x00000000018D0000-memory.dmp