bd88cf8c700d7064f3738f7349dab2224b9ff4eae69bd2459f35d19c4cf78063

Processes:

explorer.exesvchost.exe

description	ioc	process
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows NT\CurrentVersion\Winlogon\shell = "C:\\Windows\\explorer.exe, c:\\windows\\system\\explorer.exe"	explorer.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows NT\CurrentVersion\Winlogon\shell = "C:\\Windows\\explorer.exe, c:\\windows\\system\\explorer.exe"	svchost.exe

Modifies visiblity of hidden/system files in Explorer 2 TTPs 2 IoCs

evasion

Hidden Files and Directories

T1564.001

Modify Registry

Processes:

explorer.exesvchost.exe

description	ioc	process
Set value (int)	\REGISTRY\USER\S-1-5-21-330940541-141609230-1670313778-1000\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced\ShowSuperHidden = "0"	explorer.exe
Set value (int)	\REGISTRY\USER\S-1-5-21-330940541-141609230-1670313778-1000\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced\ShowSuperHidden = "0"	svchost.exe

UPX dump on OEP (original entry point) 13 IoCs

Processes:

resource	yara_rule
C:\Users\Admin\AppData\Roaming\mrsys.exe	UPX
behavioral1/memory/1152-59-0x0000000000400000-0x0000000000434000-memory.dmp	UPX
behavioral1/memory/840-55-0x0000000000400000-0x0000000000434000-memory.dmp	UPX
behavioral1/memory/2728-53-0x0000000000400000-0x0000000000434000-memory.dmp	UPX
C:\Windows\system\spoolsv.exe	UPX
\??\c:\windows\system\svchost.exe	UPX
behavioral1/memory/2080-27-0x0000000002580000-0x00000000025B4000-memory.dmp	UPX
\??\c:\windows\system\explorer.exe	UPX
behavioral1/memory/2080-14-0x0000000000400000-0x0000000000434000-memory.dmp	UPX
behavioral1/memory/1152-0-0x0000000000400000-0x0000000000434000-memory.dmp	UPX
behavioral1/memory/2080-61-0x0000000000400000-0x0000000000434000-memory.dmp	UPX
behavioral1/memory/2616-63-0x0000000000400000-0x0000000000434000-memory.dmp	UPX
behavioral1/memory/2080-72-0x0000000000400000-0x0000000000434000-memory.dmp	UPX

Modifies Installed Components in the registry 2 TTPs 8 IoCs

persistence

Registry Run Keys / Startup Folder

Modify Registry

Processes:

svchost.exeexplorer.exe

description	ioc	process
Key created	\REGISTRY\MACHINE\Software\Wow6432Node\Microsoft\Active Setup\Installed Components\{F146C9B1-VMVQ-A9RC-NUFL-D0BA00B4E999}	svchost.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Active Setup\Installed Components\{F146C9B1-VMVQ-A9RC-NUFL-D0BA00B4E999}\StubPath = "C:\\Users\\Admin\\AppData\\Roaming\\mrsys.exe MR"	svchost.exe
Key deleted	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Active Setup\Installed Components\{Y479C6D0-OTRW-U5GH-S1EE-E0AC10B4E666}	svchost.exe
Key created	\REGISTRY\MACHINE\Software\Wow6432Node\Microsoft\Active Setup\Installed Components\{Y479C6D0-OTRW-U5GH-S1EE-E0AC10B4E666}	svchost.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Active Setup\Installed Components\{Y479C6D0-OTRW-U5GH-S1EE-E0AC10B4E666}\StubPath = "C:\\Users\\Admin\\AppData\\Roaming\\mrsys.exe MR"	svchost.exe
Key deleted	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Active Setup\Installed Components\{F146C9B1-VMVQ-A9RC-NUFL-D0BA00B4E999}	svchost.exe
Key created	\REGISTRY\MACHINE\Software\Wow6432Node\Microsoft\Active Setup\Installed Components\{Y479C6D0-OTRW-U5GH-S1EE-E0AC10B4E666}	explorer.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Active Setup\Installed Components\{Y479C6D0-OTRW-U5GH-S1EE-E0AC10B4E666}\StubPath = "C:\\Users\\Admin\\AppData\\Roaming\\mrsys.exe MR"	explorer.exe

Executes dropped EXE 4 IoCs

Processes:

explorer.exespoolsv.exesvchost.exespoolsv.exe

pid process

2080 explorer.exe
840 spoolsv.exe
2616 svchost.exe
2728 spoolsv.exe

pid	process
2080	explorer.exe
840	spoolsv.exe
2616	svchost.exe
2728	spoolsv.exe

Loads dropped DLL 8 IoCs

Processes:

bd88cf8c700d7064f3738f7349dab2224b9ff4eae69bd2459f35d19c4cf78063.exeexplorer.exespoolsv.exesvchost.exe

pid	process
1152	bd88cf8c700d7064f3738f7349dab2224b9ff4eae69bd2459f35d19c4cf78063.exe
1152	bd88cf8c700d7064f3738f7349dab2224b9ff4eae69bd2459f35d19c4cf78063.exe
2080	explorer.exe
2080	explorer.exe
840	spoolsv.exe
840	spoolsv.exe
2616	svchost.exe
2616	svchost.exe

UPX packed file 13 IoCs

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

upx

Processes:

resource	yara_rule
C:\Users\Admin\AppData\Roaming\mrsys.exe	upx
behavioral1/memory/1152-59-0x0000000000400000-0x0000000000434000-memory.dmp	upx
behavioral1/memory/840-55-0x0000000000400000-0x0000000000434000-memory.dmp	upx
behavioral1/memory/2728-53-0x0000000000400000-0x0000000000434000-memory.dmp	upx
C:\Windows\system\spoolsv.exe	upx
\??\c:\windows\system\svchost.exe	upx
behavioral1/memory/2080-27-0x0000000002580000-0x00000000025B4000-memory.dmp	upx
\??\c:\windows\system\explorer.exe	upx
behavioral1/memory/2080-14-0x0000000000400000-0x0000000000434000-memory.dmp	upx
behavioral1/memory/1152-0-0x0000000000400000-0x0000000000434000-memory.dmp	upx
behavioral1/memory/2080-61-0x0000000000400000-0x0000000000434000-memory.dmp	upx
behavioral1/memory/2616-63-0x0000000000400000-0x0000000000434000-memory.dmp	upx
behavioral1/memory/2080-72-0x0000000000400000-0x0000000000434000-memory.dmp	upx

Adds Run key to start application 2 TTPs 4 IoCs

persistence

Registry Run Keys / Startup Folder

Modify Registry

Processes:

svchost.exeexplorer.exe

description	ioc	process
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\RunOnce\Explorer = "c:\\windows\\system\\explorer.exe RO"	svchost.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\RunOnce\Svchost = "c:\\windows\\system\\svchost.exe RO"	svchost.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\RunOnce\Explorer = "c:\\windows\\system\\explorer.exe RO"	explorer.exe
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\RunOnce\Svchost = "c:\\windows\\system\\svchost.exe RO"	explorer.exe

Drops file in Windows directory 6 IoCs

Processes:

bd88cf8c700d7064f3738f7349dab2224b9ff4eae69bd2459f35d19c4cf78063.exeexplorer.exespoolsv.exesvchost.exe

description	ioc	process
File opened for modification	\??\c:\windows\system\explorer.exe	bd88cf8c700d7064f3738f7349dab2224b9ff4eae69bd2459f35d19c4cf78063.exe
File opened for modification	\??\c:\windows\system\spoolsv.exe	explorer.exe
File opened for modification	\??\c:\windows\system\svchost.exe	spoolsv.exe
File opened for modification	\??\c:\windows\system\explorer.exe	explorer.exe
File opened for modification	\??\c:\windows\system\svchost.exe	svchost.exe
File opened for modification	C:\Windows\system\udsys.exe	explorer.exe

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

System Information Discovery
T1082

Suspicious behavior: EnumeratesProcesses 64 IoCs

Processes:

bd88cf8c700d7064f3738f7349dab2224b9ff4eae69bd2459f35d19c4cf78063.exeexplorer.exesvchost.exe

pid	process
1152	bd88cf8c700d7064f3738f7349dab2224b9ff4eae69bd2459f35d19c4cf78063.exe
2080	explorer.exe
2080	explorer.exe
2080	explorer.exe
2616	svchost.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe
2080	explorer.exe
2616	svchost.exe

Suspicious behavior: GetForegroundWindowSpam 2 IoCs

Processes:

explorer.exesvchost.exe

pid process

2080 explorer.exe
2616 svchost.exe

pid	process
2080	explorer.exe
2616	svchost.exe

Suspicious use of SetWindowsHookEx 12 IoCs

Processes:

bd88cf8c700d7064f3738f7349dab2224b9ff4eae69bd2459f35d19c4cf78063.exeexplorer.exespoolsv.exesvchost.exespoolsv.exe

pid	process
1152	bd88cf8c700d7064f3738f7349dab2224b9ff4eae69bd2459f35d19c4cf78063.exe
1152	bd88cf8c700d7064f3738f7349dab2224b9ff4eae69bd2459f35d19c4cf78063.exe
2080	explorer.exe
2080	explorer.exe
840	spoolsv.exe
840	spoolsv.exe
2616	svchost.exe
2616	svchost.exe
2728	spoolsv.exe
2728	spoolsv.exe
2080	explorer.exe
2080	explorer.exe

Suspicious use of WriteProcessMemory 28 IoCs

Processes:

bd88cf8c700d7064f3738f7349dab2224b9ff4eae69bd2459f35d19c4cf78063.exeexplorer.exespoolsv.exesvchost.exe

description	pid	process	target process
PID 1152 wrote to memory of 2080	1152	bd88cf8c700d7064f3738f7349dab2224b9ff4eae69bd2459f35d19c4cf78063.exe	explorer.exe
PID 1152 wrote to memory of 2080	1152	bd88cf8c700d7064f3738f7349dab2224b9ff4eae69bd2459f35d19c4cf78063.exe	explorer.exe
PID 1152 wrote to memory of 2080	1152	bd88cf8c700d7064f3738f7349dab2224b9ff4eae69bd2459f35d19c4cf78063.exe	explorer.exe
PID 1152 wrote to memory of 2080	1152	bd88cf8c700d7064f3738f7349dab2224b9ff4eae69bd2459f35d19c4cf78063.exe	explorer.exe
PID 2080 wrote to memory of 840	2080	explorer.exe	spoolsv.exe
PID 2080 wrote to memory of 840	2080	explorer.exe	spoolsv.exe
PID 2080 wrote to memory of 840	2080	explorer.exe	spoolsv.exe
PID 2080 wrote to memory of 840	2080	explorer.exe	spoolsv.exe
PID 840 wrote to memory of 2616	840	spoolsv.exe	svchost.exe
PID 840 wrote to memory of 2616	840	spoolsv.exe	svchost.exe
PID 840 wrote to memory of 2616	840	spoolsv.exe	svchost.exe
PID 840 wrote to memory of 2616	840	spoolsv.exe	svchost.exe
PID 2616 wrote to memory of 2728	2616	svchost.exe	spoolsv.exe
PID 2616 wrote to memory of 2728	2616	svchost.exe	spoolsv.exe
PID 2616 wrote to memory of 2728	2616	svchost.exe	spoolsv.exe
PID 2616 wrote to memory of 2728	2616	svchost.exe	spoolsv.exe
PID 2616 wrote to memory of 2440	2616	svchost.exe	at.exe
PID 2616 wrote to memory of 2440	2616	svchost.exe	at.exe
PID 2616 wrote to memory of 2440	2616	svchost.exe	at.exe
PID 2616 wrote to memory of 2440	2616	svchost.exe	at.exe
PID 2616 wrote to memory of 1924	2616	svchost.exe	at.exe
PID 2616 wrote to memory of 1924	2616	svchost.exe	at.exe
PID 2616 wrote to memory of 1924	2616	svchost.exe	at.exe
PID 2616 wrote to memory of 1924	2616	svchost.exe	at.exe
PID 2616 wrote to memory of 2132	2616	svchost.exe	at.exe
PID 2616 wrote to memory of 2132	2616	svchost.exe	at.exe
PID 2616 wrote to memory of 2132	2616	svchost.exe	at.exe
PID 2616 wrote to memory of 2132	2616	svchost.exe	at.exe

C:\Users\Admin\AppData\Local\Temp\bd88cf8c700d7064f3738f7349dab2224b9ff4eae69bd2459f35d19c4cf78063.exe
"C:\Users\Admin\AppData\Local\Temp\bd88cf8c700d7064f3738f7349dab2224b9ff4eae69bd2459f35d19c4cf78063.exe"
1⤵
- Loads dropped DLL
- Drops file in Windows directory
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of SetWindowsHookEx
- Suspicious use of WriteProcessMemory
PID:1152
- \??\c:\windows\system\explorer.exe
  c:\windows\system\explorer.exe
  2⤵
  - Modifies WinLogon for persistence
  - Modifies visiblity of hidden/system files in Explorer
  - Modifies Installed Components in the registry
  - Executes dropped EXE
  - Loads dropped DLL
  - Adds Run key to start application
  - Drops file in Windows directory
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious behavior: GetForegroundWindowSpam
  - Suspicious use of SetWindowsHookEx
  - Suspicious use of WriteProcessMemory
  PID:2080
- - \??\c:\windows\system\spoolsv.exe
    c:\windows\system\spoolsv.exe SE
    3⤵
    - Executes dropped EXE
    - Loads dropped DLL
    - Drops file in Windows directory
    - Suspicious use of SetWindowsHookEx
    - Suspicious use of WriteProcessMemory
    PID:840
  - - \??\c:\windows\system\svchost.exe
      c:\windows\system\svchost.exe
      4⤵
      Modifies WinLogon for persistence
      Modifies visiblity of hidden/system files in Explorer
      Modifies Installed Components in the registry
      Executes dropped EXE
      Loads dropped DLL
      Adds Run key to start application
      Drops file in Windows directory
      Suspicious behavior: EnumeratesProcesses
      Suspicious behavior: GetForegroundWindowSpam
      Suspicious use of SetWindowsHookEx
      Suspicious use of WriteProcessMemory
      PID:2616
    - - \??\c:\windows\system\spoolsv.exe
        
        c:\windows\system\spoolsv.exe PR
        5⤵
        Executes dropped EXE
        Suspicious use of SetWindowsHookEx
        
        PID:2728
    - - C:\Windows\SysWOW64\at.exe
        
        at 02:32 /interactive /every:M,T,W,Th,F,S,Su c:\windows\system\svchost.exe
        5⤵
        
        PID:2440
    - - C:\Windows\SysWOW64\at.exe
        
        at 02:33 /interactive /every:M,T,W,Th,F,S,Su c:\windows\system\svchost.exe
        5⤵
        
        PID:1924
    - - C:\Windows\SysWOW64\at.exe
        
        at 02:34 /interactive /every:M,T,W,Th,F,S,Su c:\windows\system\svchost.exe
        5⤵
        
        PID:2132

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Persistence

Boot or Logon Autostart Execution

3

T1547

Registry Run Keys / Startup Folder

2

Winlogon Helper DLL

T1547.004

Privilege Escalation

Boot or Logon Autostart Execution

3

T1547

Registry Run Keys / Startup Folder

2

Winlogon Helper DLL

T1547.004

Defense Evasion

Hide Artifacts

T1564

Hidden Files and Directories

Modify Registry

Credential Access

Discovery

System Information Discovery