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
Suspicious use of SetWindowsHookEx
Creates scheduled task(s)
Suspicious use of AdjustPrivilegeToken
Suspicious use of WriteProcessMemory
Uses Task Scheduler COM API
MITRE ATT&CK
Enterprise Matrix V15
Analysis: static1
Detonation Overview
Reported
2024-03-31 00:36
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: behavioral2
Detonation Overview
Submitted
2024-03-31 00:36
Reported
2024-03-31 01:06
Platform
win10v2004-20240226-en
Max time kernel
1794s
Max time network
1803s
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 3484 wrote to memory of 4500 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 3484 wrote to memory of 4500 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 3484 wrote to memory of 2816 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 3484 wrote to memory of 2816 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 2816 wrote to memory of 4580 | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 2816 wrote to memory of 4580 | 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:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe
"C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe" --type=utility --utility-sub-type=asset_store.mojom.AssetStoreService --lang=en-US --service-sandbox-type=asset_store_service --no-appcompat-clear --mojo-platform-channel-handle=3556 --field-trial-handle=2228,i,521073434451423547,2311651514500527526,262144 --variations-seed-version /prefetch:8
C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe
"C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe" --type=utility --utility-sub-type=asset_store.mojom.AssetStoreService --lang=en-US --service-sandbox-type=asset_store_service --no-appcompat-clear --mojo-platform-channel-handle=3780 --field-trial-handle=2228,i,521073434451423547,2311651514500527526,262144 --variations-seed-version /prefetch:8
Network
| Country | Destination | Domain | Proto |
| US | 20.231.121.79:80 | tcp | |
| US | 8.8.8.8:53 | 209.205.72.20.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 240.221.184.93.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 76.32.126.40.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 | 183.142.211.20.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 13.227.111.52.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 86.23.85.13.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 198.187.3.20.in-addr.arpa | udp |
| US | 13.107.246.64:443 | tcp | |
| US | 8.8.8.8:53 | 18.134.221.88.in-addr.arpa | udp |
| US | 8.8.8.8:53 | chromewebstore.googleapis.com | udp |
| US | 8.8.8.8:53 | chromewebstore.googleapis.com | udp |
| NL | 172.217.23.202:443 | chromewebstore.googleapis.com | tcp |
| US | 8.8.8.8:53 | 202.23.217.172.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 41.173.79.40.in-addr.arpa | udp |
Files
memory/3484-0-0x0000000000F50000-0x0000000001274000-memory.dmp
memory/3484-1-0x00007FFFB91E0000-0x00007FFFB9CA1000-memory.dmp
memory/3484-2-0x000000001BEE0000-0x000000001BEF0000-memory.dmp
C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe
| MD5 | 57045c2bf3377b12aa5abce21cc0a99d |
| SHA1 | 217202ed404f25fc550ad70fd7066b0fe8773ef9 |
| SHA256 | f2e04196e1353ad216e077e0aeb2e1ab8ee93b8b16b205422b4cc6d8adc50cc2 |
| SHA512 | 9ab46cc194eeaabb75777457a01328f5a8d2ebf604efba0623575cf25c04e206e416ee72db17e3c92a9d363330f82fa3ce2aac64c2a4a61d4dce34d79b73366e |
memory/3484-9-0x00007FFFB91E0000-0x00007FFFB9CA1000-memory.dmp
memory/2816-8-0x00007FFFB91E0000-0x00007FFFB9CA1000-memory.dmp
memory/2816-10-0x0000000000BF0000-0x0000000000C00000-memory.dmp
memory/2816-11-0x000000001B7E0000-0x000000001B830000-memory.dmp
memory/2816-12-0x000000001B8F0000-0x000000001B9A2000-memory.dmp
memory/2816-15-0x000000001B890000-0x000000001B8A2000-memory.dmp
memory/2816-16-0x000000001C3F0000-0x000000001C42C000-memory.dmp
memory/2816-17-0x00007FFFB91E0000-0x00007FFFB9CA1000-memory.dmp
memory/2816-18-0x0000000000BF0000-0x0000000000C00000-memory.dmp
Analysis: behavioral3
Detonation Overview
Submitted
2024-03-31 00:36
Reported
2024-03-31 01:06
Platform
win11-20240221-en
Max time kernel
451s
Max time network
1786s
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 780 wrote to memory of 1596 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 780 wrote to memory of 1596 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 780 wrote to memory of 3876 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 780 wrote to memory of 3876 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 3876 wrote to memory of 904 | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 3876 wrote to memory of 904 | 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 | 41.134.221.88.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 90.57.201.195.in-addr.arpa | udp |
Files
memory/780-0-0x0000000000F40000-0x0000000001264000-memory.dmp
memory/780-1-0x00007FF9772B0000-0x00007FF977D72000-memory.dmp
memory/780-2-0x0000000001AE0000-0x0000000001AF0000-memory.dmp
C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe
| MD5 | 57045c2bf3377b12aa5abce21cc0a99d |
| SHA1 | 217202ed404f25fc550ad70fd7066b0fe8773ef9 |
| SHA256 | f2e04196e1353ad216e077e0aeb2e1ab8ee93b8b16b205422b4cc6d8adc50cc2 |
| SHA512 | 9ab46cc194eeaabb75777457a01328f5a8d2ebf604efba0623575cf25c04e206e416ee72db17e3c92a9d363330f82fa3ce2aac64c2a4a61d4dce34d79b73366e |
memory/3876-9-0x00007FF9772B0000-0x00007FF977D72000-memory.dmp
memory/780-8-0x00007FF9772B0000-0x00007FF977D72000-memory.dmp
memory/3876-10-0x00000000017C0000-0x00000000017D0000-memory.dmp
memory/3876-11-0x000000001BD90000-0x000000001BDE0000-memory.dmp
memory/3876-12-0x000000001C8E0000-0x000000001C992000-memory.dmp
memory/3876-15-0x000000001C840000-0x000000001C852000-memory.dmp
memory/3876-16-0x000000001C8A0000-0x000000001C8DC000-memory.dmp
memory/3876-17-0x00007FF9772B0000-0x00007FF977D72000-memory.dmp
memory/3876-18-0x00000000017C0000-0x00000000017D0000-memory.dmp
Analysis: behavioral1
Detonation Overview
Submitted
2024-03-31 00:36
Reported
2024-03-31 01:06
Platform
win10-20240214-en
Max time kernel
362s
Max time network
1784s
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 4372 wrote to memory of 4416 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 4372 wrote to memory of 4416 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 4372 wrote to memory of 1460 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 4372 wrote to memory of 1460 | N/A | C:\Users\Admin\AppData\Local\Temp\Client-built.exe | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe |
| PID 1460 wrote to memory of 2188 | N/A | C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe | C:\Windows\SYSTEM32\schtasks.exe |
| PID 1460 wrote to memory of 2188 | 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 | 19.229.111.52.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 26.73.42.20.in-addr.arpa | udp |
| US | 8.8.8.8:53 | 65.192.122.92.in-addr.arpa | udp |
Files
memory/4372-0-0x0000000000960000-0x0000000000C84000-memory.dmp
memory/4372-1-0x00007FF90A4E0000-0x00007FF90AECC000-memory.dmp
memory/4372-2-0x000000001B9B0000-0x000000001B9C0000-memory.dmp
C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe
| MD5 | 57045c2bf3377b12aa5abce21cc0a99d |
| SHA1 | 217202ed404f25fc550ad70fd7066b0fe8773ef9 |
| SHA256 | f2e04196e1353ad216e077e0aeb2e1ab8ee93b8b16b205422b4cc6d8adc50cc2 |
| SHA512 | 9ab46cc194eeaabb75777457a01328f5a8d2ebf604efba0623575cf25c04e206e416ee72db17e3c92a9d363330f82fa3ce2aac64c2a4a61d4dce34d79b73366e |
memory/1460-9-0x00007FF90A4E0000-0x00007FF90AECC000-memory.dmp
memory/4372-8-0x00007FF90A4E0000-0x00007FF90AECC000-memory.dmp
memory/1460-10-0x000000001B8B0000-0x000000001B8C0000-memory.dmp
memory/1460-11-0x000000001BF10000-0x000000001BF60000-memory.dmp
memory/1460-12-0x000000001C020000-0x000000001C0D2000-memory.dmp
memory/1460-15-0x000000001BFD0000-0x000000001BFE2000-memory.dmp
memory/1460-16-0x000000001CB50000-0x000000001CB8E000-memory.dmp
memory/1460-17-0x00007FF90A4E0000-0x00007FF90AECC000-memory.dmp
memory/1460-18-0x000000001B8B0000-0x000000001B8C0000-memory.dmp