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
Suspicious use of AdjustPrivilegeToken
Suspicious use of SetWindowsHookEx
Suspicious use of WriteProcessMemory
Creates scheduled task(s)
Uses Task Scheduler COM API
MITRE ATT&CK
Enterprise Matrix V15
Analysis: static1
Detonation Overview
Reported
2024-03-31 00:42
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: behavioral3
Detonation Overview
Submitted
2024-03-31 00:42
Reported
2024-03-31 01:12
Platform
win11-20240221-en
Max time kernel
1710s
Max time network
1790s
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 1540 wrote to memory of 4028 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 1540 wrote to memory of 4028 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 1540 wrote to memory of 1876 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 1540 wrote to memory of 1876 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 1876 wrote to memory of 2024 | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 1876 wrote to memory of 2024 | 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 | 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 |
Files
memory/1540-0-0x0000000000310000-0x0000000000634000-memory.dmp
memory/1540-1-0x00007FFDEF490000-0x00007FFDEFF52000-memory.dmp
memory/1540-2-0x000000001B240000-0x000000001B250000-memory.dmp
C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe
| MD5 | 57045c2bf3377b12aa5abce21cc0a99d |
| SHA1 | 217202ed404f25fc550ad70fd7066b0fe8773ef9 |
| SHA256 | f2e04196e1353ad216e077e0aeb2e1ab8ee93b8b16b205422b4cc6d8adc50cc2 |
| SHA512 | 9ab46cc194eeaabb75777457a01328f5a8d2ebf604efba0623575cf25c04e206e416ee72db17e3c92a9d363330f82fa3ce2aac64c2a4a61d4dce34d79b73366e |
memory/1876-8-0x00007FFDEF490000-0x00007FFDEFF52000-memory.dmp
memory/1540-9-0x00007FFDEF490000-0x00007FFDEFF52000-memory.dmp
memory/1876-10-0x000000001BAB0000-0x000000001BAC0000-memory.dmp
memory/1876-11-0x000000001C5B0000-0x000000001C600000-memory.dmp
memory/1876-12-0x000000001C6C0000-0x000000001C772000-memory.dmp
memory/1876-15-0x000000001C620000-0x000000001C632000-memory.dmp
memory/1876-16-0x000000001C680000-0x000000001C6BC000-memory.dmp
memory/1876-17-0x00007FFDEF490000-0x00007FFDEFF52000-memory.dmp
memory/1876-18-0x000000001BAB0000-0x000000001BAC0000-memory.dmp
Analysis: behavioral1
Detonation Overview
Submitted
2024-03-31 00:42
Reported
2024-03-31 01:12
Platform
win10-20240221-en
Max time kernel
1710s
Max time network
1790s
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 4576 wrote to memory of 3364 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 4576 wrote to memory of 3364 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 4576 wrote to memory of 3376 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 4576 wrote to memory of 3376 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 3376 wrote to memory of 1532 | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 3376 wrote to memory of 1532 | 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 | 41.134.221.88.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 90.57.201.195.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 26.178.89.13.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 |
Files
memory/4576-0-0x0000000000D60000-0x0000000001084000-memory.dmp
memory/4576-1-0x00007FFAB2650000-0x00007FFAB303C000-memory.dmp
memory/4576-2-0x0000000003180000-0x0000000003190000-memory.dmp
C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe
| MD5 | 57045c2bf3377b12aa5abce21cc0a99d |
| SHA1 | 217202ed404f25fc550ad70fd7066b0fe8773ef9 |
| SHA256 | f2e04196e1353ad216e077e0aeb2e1ab8ee93b8b16b205422b4cc6d8adc50cc2 |
| SHA512 | 9ab46cc194eeaabb75777457a01328f5a8d2ebf604efba0623575cf25c04e206e416ee72db17e3c92a9d363330f82fa3ce2aac64c2a4a61d4dce34d79b73366e |
memory/3376-9-0x00007FFAB2650000-0x00007FFAB303C000-memory.dmp
memory/4576-8-0x00007FFAB2650000-0x00007FFAB303C000-memory.dmp
memory/3376-10-0x0000000002E00000-0x0000000002E10000-memory.dmp
memory/3376-11-0x000000001BE00000-0x000000001BE50000-memory.dmp
memory/3376-12-0x000000001BF10000-0x000000001BFC2000-memory.dmp
memory/3376-15-0x000000001BEB0000-0x000000001BEC2000-memory.dmp
memory/3376-16-0x000000001CA00000-0x000000001CA3E000-memory.dmp
memory/3376-17-0x00007FFAB2650000-0x00007FFAB303C000-memory.dmp
memory/3376-18-0x0000000002E00000-0x0000000002E10000-memory.dmp
Analysis: behavioral2
Detonation Overview
Submitted
2024-03-31 00:42
Reported
2024-03-31 01:12
Platform
win10v2004-20240226-en
Max time kernel
1710s
Max time network
1790s
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 4208 wrote to memory of 3200 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 4208 wrote to memory of 3200 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 4208 wrote to memory of 1668 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 4208 wrote to memory of 1668 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 1668 wrote to memory of 4404 | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 1668 wrote to memory of 4404 | 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 | 40.134.221.88.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 217.106.137.52.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 0.159.190.20.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 149.220.183.52.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 | 103.169.127.40.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 198.187.3.20.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 217.135.221.88.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 201.203.100.95.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 0.204.248.87.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 9.179.89.13.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 |
Files
memory/4208-0-0x0000000000B30000-0x0000000000E54000-memory.dmp
memory/4208-1-0x00007FFBAE1F0000-0x00007FFBAECB1000-memory.dmp
memory/4208-2-0x000000001BB70000-0x000000001BB80000-memory.dmp
C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe
| MD5 | 57045c2bf3377b12aa5abce21cc0a99d |
| SHA1 | 217202ed404f25fc550ad70fd7066b0fe8773ef9 |
| SHA256 | f2e04196e1353ad216e077e0aeb2e1ab8ee93b8b16b205422b4cc6d8adc50cc2 |
| SHA512 | 9ab46cc194eeaabb75777457a01328f5a8d2ebf604efba0623575cf25c04e206e416ee72db17e3c92a9d363330f82fa3ce2aac64c2a4a61d4dce34d79b73366e |
memory/1668-9-0x00007FFBAE1F0000-0x00007FFBAECB1000-memory.dmp
memory/4208-8-0x00007FFBAE1F0000-0x00007FFBAECB1000-memory.dmp
memory/1668-10-0x000000001B7E0000-0x000000001B7F0000-memory.dmp
memory/1668-11-0x0000000002DB0000-0x0000000002E00000-memory.dmp
memory/1668-12-0x000000001C050000-0x000000001C102000-memory.dmp
memory/1668-15-0x000000001B860000-0x000000001B872000-memory.dmp
memory/1668-16-0x000000001BFD0000-0x000000001C00C000-memory.dmp
memory/1668-17-0x00007FFBAE1F0000-0x00007FFBAECB1000-memory.dmp
memory/1668-18-0x000000001B7E0000-0x000000001B7F0000-memory.dmp