Analysis Overview
SHA256
f2e04196e1353ad216e077e0aeb2e1ab8ee93b8b16b205422b4cc6d8adc50cc2
Threat Level: Known bad
The file Client-built.exe was found to be: Known bad.
Malicious Activity Summary
Quasar family
Quasar payload
Quasar RAT
Executes dropped EXE
Unsigned PE
Creates scheduled task(s)
Suspicious use of AdjustPrivilegeToken
Suspicious use of WriteProcessMemory
Uses Task Scheduler COM API
Suspicious use of SetWindowsHookEx
MITRE ATT&CK
Enterprise Matrix V15
Analysis: static1
Detonation Overview
Reported
2024-03-31 00:40
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 00:40
Reported
2024-03-31 01:10
Platform
win10-20240214-en
Max time kernel
1690s
Max time network
1792s
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 4564 wrote to memory of 3876 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 4564 wrote to memory of 3876 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 4564 wrote to memory of 4932 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 4564 wrote to memory of 4932 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 4932 wrote to memory of 824 | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 4932 wrote to memory of 824 | 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 | 40.134.221.88.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 90.57.201.195.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 29.243.111.52.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 67.112.168.52.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 240.221.184.93.in-addr.arpa | udp |
| NL | 52.142.223.178:80 | 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/4564-0-0x0000000000FA0000-0x00000000012C4000-memory.dmp
memory/4564-1-0x00007FFF710E0000-0x00007FFF71ACC000-memory.dmp
memory/4564-2-0x000000001C0A0000-0x000000001C0B0000-memory.dmp
C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe
| MD5 | 57045c2bf3377b12aa5abce21cc0a99d |
| SHA1 | 217202ed404f25fc550ad70fd7066b0fe8773ef9 |
| SHA256 | f2e04196e1353ad216e077e0aeb2e1ab8ee93b8b16b205422b4cc6d8adc50cc2 |
| SHA512 | 9ab46cc194eeaabb75777457a01328f5a8d2ebf604efba0623575cf25c04e206e416ee72db17e3c92a9d363330f82fa3ce2aac64c2a4a61d4dce34d79b73366e |
memory/4564-8-0x00007FFF710E0000-0x00007FFF71ACC000-memory.dmp
memory/4932-9-0x00007FFF710E0000-0x00007FFF71ACC000-memory.dmp
memory/4932-10-0x0000000003040000-0x0000000003050000-memory.dmp
memory/4932-11-0x000000001C2D0000-0x000000001C320000-memory.dmp
memory/4932-12-0x000000001C3E0000-0x000000001C492000-memory.dmp
memory/4932-15-0x000000001C380000-0x000000001C392000-memory.dmp
memory/4932-16-0x000000001CED0000-0x000000001CF0E000-memory.dmp
memory/4932-17-0x00007FFF710E0000-0x00007FFF71ACC000-memory.dmp
memory/4932-18-0x0000000003040000-0x0000000003050000-memory.dmp
Analysis: behavioral2
Detonation Overview
Submitted
2024-03-31 00:40
Reported
2024-03-31 01:10
Platform
win10v2004-20240226-en
Max time kernel
1793s
Max time network
1792s
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 |
| Token: SeManageVolumePrivilege | N/A | C:\Windows\System32\svchost.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 1916 wrote to memory of 2340 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 1916 wrote to memory of 2340 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 1916 wrote to memory of 1764 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 1916 wrote to memory of 1764 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 1764 wrote to memory of 1516 | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 1764 wrote to memory of 1516 | 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
C:\Windows\system32\rundll32.exe
"C:\Windows\system32\rundll32.exe" "C:\Windows\SYSTEM32\EDGEHTML.dll",#141 Microsoft.VCLibs.140.00_8wekyb3d8bbwe
C:\Windows\System32\svchost.exe
C:\Windows\System32\svchost.exe -k UnistackSvcGroup
Network
| Country | Destination | Domain | Proto |
| US | 8.8.8.8:53 | 183.142.211.20.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 41.134.221.88.in-addr.arpa | udp |
| GB | 140.238.91.110:44867 | tcp | |
| US | 8.8.8.8:53 | 4.159.190.20.in-addr.arpa | udp |
| 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 | 133.211.185.52.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 26.165.165.52.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 171.39.242.20.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 18.134.221.88.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 40.134.221.88.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 48.229.111.52.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 9.179.89.13.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 157.123.68.40.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 9.228.82.20.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 167.161.23.2.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 56.126.166.20.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 100.5.17.2.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 119.110.54.20.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 217.135.221.88.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 240.221.184.93.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 32.134.221.88.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 172.210.232.199.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/1916-0-0x0000000000090000-0x00000000003B4000-memory.dmp
memory/1916-1-0x00007FF918FF0000-0x00007FF919AB1000-memory.dmp
memory/1916-2-0x000000001AFE0000-0x000000001AFF0000-memory.dmp
C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe
| MD5 | 57045c2bf3377b12aa5abce21cc0a99d |
| SHA1 | 217202ed404f25fc550ad70fd7066b0fe8773ef9 |
| SHA256 | f2e04196e1353ad216e077e0aeb2e1ab8ee93b8b16b205422b4cc6d8adc50cc2 |
| SHA512 | 9ab46cc194eeaabb75777457a01328f5a8d2ebf604efba0623575cf25c04e206e416ee72db17e3c92a9d363330f82fa3ce2aac64c2a4a61d4dce34d79b73366e |
memory/1916-8-0x00007FF918FF0000-0x00007FF919AB1000-memory.dmp
memory/1764-9-0x00007FF918FF0000-0x00007FF919AB1000-memory.dmp
memory/1764-10-0x000000001BEF0000-0x000000001BF00000-memory.dmp
memory/1764-11-0x000000001BE50000-0x000000001BEA0000-memory.dmp
memory/1764-12-0x000000001C810000-0x000000001C8C2000-memory.dmp
memory/1764-15-0x000000001BF00000-0x000000001BF12000-memory.dmp
memory/1764-16-0x000000001C790000-0x000000001C7CC000-memory.dmp
memory/1764-17-0x000000001D210000-0x000000001D312000-memory.dmp
memory/1764-19-0x00007FF918FF0000-0x00007FF919AB1000-memory.dmp
memory/1764-20-0x000000001BEF0000-0x000000001BF00000-memory.dmp
Analysis: behavioral3
Detonation Overview
Submitted
2024-03-31 00:40
Reported
2024-03-31 01:10
Platform
win11-20240221-en
Max time kernel
1690s
Max time network
1792s
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 4824 wrote to memory of 380 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 4824 wrote to memory of 380 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 4824 wrote to memory of 1272 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 4824 wrote to memory of 1272 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 1272 wrote to memory of 4664 | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 1272 wrote to memory of 4664 | 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 | 110.91.238.140.in-addr.arpa | udp |
| DE | 195.201.57.90:443 | ipwho.is | tcp |
| US | 52.111.227.13:443 | 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/4824-0-0x0000000000250000-0x0000000000574000-memory.dmp
memory/4824-1-0x00007FFA2CAE0000-0x00007FFA2D5A2000-memory.dmp
memory/4824-2-0x000000001B490000-0x000000001B4A0000-memory.dmp
C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe
| MD5 | 57045c2bf3377b12aa5abce21cc0a99d |
| SHA1 | 217202ed404f25fc550ad70fd7066b0fe8773ef9 |
| SHA256 | f2e04196e1353ad216e077e0aeb2e1ab8ee93b8b16b205422b4cc6d8adc50cc2 |
| SHA512 | 9ab46cc194eeaabb75777457a01328f5a8d2ebf604efba0623575cf25c04e206e416ee72db17e3c92a9d363330f82fa3ce2aac64c2a4a61d4dce34d79b73366e |
memory/4824-7-0x00007FFA2CAE0000-0x00007FFA2D5A2000-memory.dmp
memory/1272-9-0x00007FFA2CAE0000-0x00007FFA2D5A2000-memory.dmp
memory/1272-10-0x0000000001F60000-0x0000000001F70000-memory.dmp
memory/1272-11-0x000000001C9F0000-0x000000001CA40000-memory.dmp
memory/1272-12-0x000000001CB00000-0x000000001CBB2000-memory.dmp
memory/1272-15-0x000000001CAC0000-0x000000001CAD2000-memory.dmp
memory/1272-16-0x000000001D250000-0x000000001D28C000-memory.dmp
memory/1272-17-0x00007FFA2CAE0000-0x00007FFA2D5A2000-memory.dmp
memory/1272-18-0x0000000001F60000-0x0000000001F70000-memory.dmp