darkcomet | a91538569450d03ccab04981d182a90feee1ef623825849c05df3826cbeec25d

System Information Discovery

description	ioc	Process
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\SystemBiosDate	mcsft.exe

Executes dropped EXE 2 IoCs

pid	Process
2872	mcsft.exe
2980	mcsft.exe

Loads dropped DLL 6 IoCs

pid	Process
2256	48bfbcdac6fefdc5f4f94a6ffdb0c0b0N.exe
2256	48bfbcdac6fefdc5f4f94a6ffdb0c0b0N.exe
2256	48bfbcdac6fefdc5f4f94a6ffdb0c0b0N.exe
2256	48bfbcdac6fefdc5f4f94a6ffdb0c0b0N.exe
2256	48bfbcdac6fefdc5f4f94a6ffdb0c0b0N.exe
2872	mcsft.exe

UPX packed file 21 IoCs

Detects executables packed with UPX/modified UPX open source packer.

upx

resource	yara_rule
behavioral1/memory/2256-0-0x0000000000400000-0x00000000007C8000-memory.dmp	upx
behavioral1/files/0x0009000000018ed5-27.dat	upx
behavioral1/memory/2980-51-0x0000000000400000-0x00000000004B5000-memory.dmp	upx
behavioral1/memory/2256-43-0x0000000000400000-0x00000000007C8000-memory.dmp	upx
behavioral1/memory/2980-54-0x0000000000400000-0x00000000004B5000-memory.dmp	upx
behavioral1/memory/2872-57-0x0000000000400000-0x00000000007C8000-memory.dmp	upx
behavioral1/memory/2980-55-0x0000000000400000-0x00000000004B5000-memory.dmp	upx
behavioral1/memory/2872-53-0x0000000000400000-0x00000000007C8000-memory.dmp	upx
behavioral1/memory/2980-58-0x0000000000400000-0x00000000004B5000-memory.dmp	upx
behavioral1/memory/2980-60-0x0000000000400000-0x00000000004B5000-memory.dmp	upx
behavioral1/memory/2980-61-0x0000000000400000-0x00000000004B5000-memory.dmp	upx
behavioral1/memory/2980-59-0x0000000000400000-0x00000000004B5000-memory.dmp	upx
behavioral1/memory/2980-64-0x0000000000400000-0x00000000004B5000-memory.dmp	upx
behavioral1/memory/2980-63-0x0000000000400000-0x00000000004B5000-memory.dmp	upx
behavioral1/memory/2980-62-0x0000000000400000-0x00000000004B5000-memory.dmp	upx
behavioral1/memory/2980-65-0x0000000000400000-0x00000000004B5000-memory.dmp	upx
behavioral1/memory/2980-67-0x0000000000400000-0x00000000004B5000-memory.dmp	upx
behavioral1/memory/2980-69-0x0000000000400000-0x00000000004B5000-memory.dmp	upx
behavioral1/memory/2980-71-0x0000000000400000-0x00000000004B5000-memory.dmp	upx
behavioral1/memory/2980-73-0x0000000000400000-0x00000000004B5000-memory.dmp	upx
behavioral1/memory/2980-75-0x0000000000400000-0x00000000004B5000-memory.dmp	upx

Adds Run key to start application 2 TTPs 1 IoCs

persistence

Registry Run Keys / Startup Folder

T1547.001

Modify Registry

T1112

description	ioc	Process
Set value (str)	\REGISTRY\USER\S-1-5-21-2212144002-1172735686-1556890956-1000\Software\Microsoft\Windows\CurrentVersion\Run\Mcrosoft = "C:\\Users\\Admin\\AppData\\Roaming\\mcsft.exe"	reg.exe

Suspicious use of SetThreadContext 1 IoCs

description	pid	Process	procid_target
PID 2872 set thread context of 2980	2872	mcsft.exe	33

Enumerates physical storage devices 1 TTPs
Attempts to interact with connected storage/optical drive(s).

System Information Discovery
T1082

System Location Discovery: System Language Discovery 1 TTPs 5 IoCs

Attempt gather information about the system language of a victim in order to infer the geographical location of that host.

discovery

System Language Discovery

T1614.001

description	ioc	Process
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	48bfbcdac6fefdc5f4f94a6ffdb0c0b0N.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	cmd.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	reg.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	mcsft.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	mcsft.exe

Checks processor information in registry 2 TTPs 4 IoCs

Processor information is often read in order to detect sandboxing environments.

Query Registry

System Information Discovery

description	ioc	Process
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0\ProcessorNameString	mcsft.exe
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0\Identifier	mcsft.exe
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0\VendorIdentifier	mcsft.exe
Key opened	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0	mcsft.exe

Enumerates system info in registry 2 TTPs 1 IoCs

Query Registry

System Information Discovery

description	ioc	Process
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\Identifier	mcsft.exe

Suspicious use of AdjustPrivilegeToken 23 IoCs

description	pid	Process
Token: SeIncreaseQuotaPrivilege	2980	mcsft.exe
Token: SeSecurityPrivilege	2980	mcsft.exe
Token: SeTakeOwnershipPrivilege	2980	mcsft.exe
Token: SeLoadDriverPrivilege	2980	mcsft.exe
Token: SeSystemProfilePrivilege	2980	mcsft.exe
Token: SeSystemtimePrivilege	2980	mcsft.exe
Token: SeProfSingleProcessPrivilege	2980	mcsft.exe
Token: SeIncBasePriorityPrivilege	2980	mcsft.exe
Token: SeCreatePagefilePrivilege	2980	mcsft.exe
Token: SeBackupPrivilege	2980	mcsft.exe
Token: SeRestorePrivilege	2980	mcsft.exe
Token: SeShutdownPrivilege	2980	mcsft.exe
Token: SeDebugPrivilege	2980	mcsft.exe
Token: SeSystemEnvironmentPrivilege	2980	mcsft.exe
Token: SeChangeNotifyPrivilege	2980	mcsft.exe
Token: SeRemoteShutdownPrivilege	2980	mcsft.exe
Token: SeUndockPrivilege	2980	mcsft.exe
Token: SeManageVolumePrivilege	2980	mcsft.exe
Token: SeImpersonatePrivilege	2980	mcsft.exe
Token: SeCreateGlobalPrivilege	2980	mcsft.exe
Token: 33	2980	mcsft.exe
Token: 34	2980	mcsft.exe
Token: 35	2980	mcsft.exe

Suspicious use of SetWindowsHookEx 3 IoCs

pid	Process
2256	48bfbcdac6fefdc5f4f94a6ffdb0c0b0N.exe
2872	mcsft.exe
2980	mcsft.exe

Suspicious use of WriteProcessMemory 21 IoCs

description	pid	Process	procid_target
PID 2256 wrote to memory of 2108	2256	48bfbcdac6fefdc5f4f94a6ffdb0c0b0N.exe	29
PID 2256 wrote to memory of 2108	2256	48bfbcdac6fefdc5f4f94a6ffdb0c0b0N.exe	29
PID 2256 wrote to memory of 2108	2256	48bfbcdac6fefdc5f4f94a6ffdb0c0b0N.exe	29
PID 2256 wrote to memory of 2108	2256	48bfbcdac6fefdc5f4f94a6ffdb0c0b0N.exe	29
PID 2108 wrote to memory of 2304	2108	cmd.exe	31
PID 2108 wrote to memory of 2304	2108	cmd.exe	31
PID 2108 wrote to memory of 2304	2108	cmd.exe	31
PID 2108 wrote to memory of 2304	2108	cmd.exe	31
PID 2256 wrote to memory of 2872	2256	48bfbcdac6fefdc5f4f94a6ffdb0c0b0N.exe	32
PID 2256 wrote to memory of 2872	2256	48bfbcdac6fefdc5f4f94a6ffdb0c0b0N.exe	32
PID 2256 wrote to memory of 2872	2256	48bfbcdac6fefdc5f4f94a6ffdb0c0b0N.exe	32
PID 2256 wrote to memory of 2872	2256	48bfbcdac6fefdc5f4f94a6ffdb0c0b0N.exe	32
PID 2872 wrote to memory of 2980	2872	mcsft.exe	33
PID 2872 wrote to memory of 2980	2872	mcsft.exe	33
PID 2872 wrote to memory of 2980	2872	mcsft.exe	33
PID 2872 wrote to memory of 2980	2872	mcsft.exe	33
PID 2872 wrote to memory of 2980	2872	mcsft.exe	33
PID 2872 wrote to memory of 2980	2872	mcsft.exe	33
PID 2872 wrote to memory of 2980	2872	mcsft.exe	33
PID 2872 wrote to memory of 2980	2872	mcsft.exe	33
PID 2872 wrote to memory of 2980	2872	mcsft.exe	33

C:\Users\Admin\AppData\Local\Temp\48bfbcdac6fefdc5f4f94a6ffdb0c0b0N.exe
"C:\Users\Admin\AppData\Local\Temp\48bfbcdac6fefdc5f4f94a6ffdb0c0b0N.exe"
1⤵
- Loads dropped DLL
- System Location Discovery: System Language Discovery
- Suspicious use of SetWindowsHookEx
- Suspicious use of WriteProcessMemory
PID:2256
- C:\Windows\SysWOW64\cmd.exe
  cmd /c ""C:\Users\Admin\AppData\Local\Temp\RvwKV.bat" "
  2⤵
  - System Location Discovery: System Language Discovery
  - Suspicious use of WriteProcessMemory
  PID:2108
- - C:\Windows\SysWOW64\reg.exe
    REG ADD "HKCU\Software\Microsoft\Windows\CurrentVersion\Run" /v "Mcrosoft" /t REG_SZ /d "C:\Users\Admin\AppData\Roaming\mcsft.exe" /f
    3⤵
    - Adds Run key to start application
    - System Location Discovery: System Language Discovery
    PID:2304
- C:\Users\Admin\AppData\Roaming\mcsft.exe
  "C:\Users\Admin\AppData\Roaming\mcsft.exe"
  2⤵
  - Executes dropped EXE
  - Loads dropped DLL
  - Suspicious use of SetThreadContext
  - System Location Discovery: System Language Discovery
  - Suspicious use of SetWindowsHookEx
  - Suspicious use of WriteProcessMemory
  PID:2872
- - C:\Users\Admin\AppData\Roaming\mcsft.exe
    C:\Users\Admin\AppData\Roaming\mcsft.exe
    3⤵
    - Checks BIOS information in registry
    - Executes dropped EXE
    - System Location Discovery: System Language Discovery
    - Checks processor information in registry
    - Enumerates system info in registry
    - Suspicious use of AdjustPrivilegeToken
    - Suspicious use of SetWindowsHookEx
    PID:2980

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Persistence

Boot or Logon Autostart Execution

T1547

Registry Run Keys / Startup Folder

T1547.001

Privilege Escalation

Boot or Logon Autostart Execution

T1547

Registry Run Keys / Startup Folder

T1547.001

Defense Evasion

Modify Registry

T1112

Credential Access

Discovery

Query Registry

3

System Information Discovery

4

System Location Discovery

T1614

System Language Discovery