nanocore | 2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598

Bypass User Account Control

T1548.002

Disable or Modify Tools

T1562.001

Modify Registry

Processes:

2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe

description	ioc	process
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\EnableLUA = "0"	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe

Windows security bypass 2 TTPs 2 IoCs

Disable or Modify Tools

T1562.001

Modify Registry

Processes:

2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe

description	ioc	process
Key created	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows Defender\Exclusions\Paths	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows Defender\Exclusions\Paths\C:\Users\Admin\AppData\Local\Temp\2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe = "0"	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe

Command and Scripting Interpreter: PowerShell 1 TTPs 1 IoCs
Run Powershell to modify Windows Defender settings to add exclusions for file extensions, paths, and processes.
execution

PowerShell
T1059.001

Processes:

powershell.exe

pid process

3076 powershell.exe

pid	process
3076	powershell.exe

Checks computer location settings 2 TTPs 1 IoCs

Looks up country code configured in the registry, likely geofence.

Query Registry

T1012

System Information Discovery

T1082

Processes:

2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe

description	ioc	process
Key value queried	\REGISTRY\USER\S-1-5-21-464762018-485119342-1613148473-1000\Control Panel\International\Geo\Nation	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe

Windows security modification 2 TTPs 3 IoCs

Disable or Modify Tools

T1562.001

Modify Registry

Processes:

2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe

description	ioc	process
Key created	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows Defender\Exclusions\Paths	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe
Key created	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows Defender\Exclusions	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows Defender\Exclusions\Paths\C:\Users\Admin\AppData\Local\Temp\2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe = "0"	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe

Adds Run key to start application 2 TTPs 1 IoCs

persistence

Registry Run Keys / Startup Folder

T1547.001

Modify Registry

Processes:

regasm.exe

description	ioc	process
Set value (str)	\REGISTRY\MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Run\NAT Subsystem = "C:\\Program Files (x86)\\NAT Subsystem\\natss.exe"	regasm.exe

Checks whether UAC is enabled 1 TTPs 3 IoCs

System Information Discovery

T1082

Processes:

2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exeregasm.exe

description	ioc	process
Key value queried	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\EnableLUA	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\EnableLUA = "0"	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe
Key value queried	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\EnableLUA	regasm.exe

Suspicious use of SetThreadContext 1 IoCs

Processes:

2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe

description	pid	process	target process
PID 3100 set thread context of 208	3100	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe	regasm.exe

Drops file in Program Files directory 2 IoCs

Processes:

regasm.exe

description	ioc	process
File created	C:\Program Files (x86)\NAT Subsystem\natss.exe	regasm.exe
File opened for modification	C:\Program Files (x86)\NAT Subsystem\natss.exe	regasm.exe

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

System Information Discovery
T1082
Scheduled Task/Job: Scheduled Task 1 TTPs 2 IoCs
Schtasks is often used by malware for persistence or to perform post-infection execution.
persistence execution

Scheduled Task
T1053.005

Processes:

schtasks.exeschtasks.exe

pid process

1040 schtasks.exe
4620 schtasks.exe
Suspicious behavior: EnumeratesProcesses 5 IoCs

Processes:

powershell.exeregasm.exe

pid process

3076 powershell.exe
3076 powershell.exe
208 regasm.exe
208 regasm.exe
208 regasm.exe
Suspicious behavior: GetForegroundWindowSpam 1 IoCs

Processes:

regasm.exe

pid process

208 regasm.exe
Suspicious use of AdjustPrivilegeToken 2 IoCs

Processes:

powershell.exeregasm.exe

description pid process

Token: SeDebugPrivilege 3076 powershell.exe
Token: SeDebugPrivilege 208 regasm.exe

pid	process
1040	schtasks.exe
4620	schtasks.exe

pid	process
3076	powershell.exe
3076	powershell.exe
208	regasm.exe
208	regasm.exe
208	regasm.exe

pid	process
208	regasm.exe

description	pid	process
Token: SeDebugPrivilege	3076	powershell.exe
Token: SeDebugPrivilege	208	regasm.exe

Suspicious use of WriteProcessMemory 25 IoCs

Processes:

2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exeregasm.exe

description	pid	process	target process
PID 3100 wrote to memory of 3076	3100	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe	powershell.exe
PID 3100 wrote to memory of 3076	3100	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe	powershell.exe
PID 3100 wrote to memory of 840	3100	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe	msbuild.exe
PID 3100 wrote to memory of 840	3100	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe	msbuild.exe
PID 3100 wrote to memory of 840	3100	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe	msbuild.exe
PID 3100 wrote to memory of 3916	3100	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe	installutil.exe
PID 3100 wrote to memory of 3916	3100	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe	installutil.exe
PID 3100 wrote to memory of 3916	3100	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe	installutil.exe
PID 3100 wrote to memory of 208	3100	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe	regasm.exe
PID 3100 wrote to memory of 208	3100	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe	regasm.exe
PID 3100 wrote to memory of 208	3100	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe	regasm.exe
PID 3100 wrote to memory of 208	3100	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe	regasm.exe
PID 3100 wrote to memory of 208	3100	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe	regasm.exe
PID 3100 wrote to memory of 208	3100	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe	regasm.exe
PID 3100 wrote to memory of 208	3100	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe	regasm.exe
PID 3100 wrote to memory of 208	3100	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe	regasm.exe
PID 3100 wrote to memory of 3012	3100	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe	regasm.exe
PID 3100 wrote to memory of 3012	3100	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe	regasm.exe
PID 3100 wrote to memory of 3012	3100	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe	regasm.exe
PID 208 wrote to memory of 1040	208	regasm.exe	schtasks.exe
PID 208 wrote to memory of 1040	208	regasm.exe	schtasks.exe
PID 208 wrote to memory of 1040	208	regasm.exe	schtasks.exe
PID 208 wrote to memory of 4620	208	regasm.exe	schtasks.exe
PID 208 wrote to memory of 4620	208	regasm.exe	schtasks.exe
PID 208 wrote to memory of 4620	208	regasm.exe	schtasks.exe

System policy modification 1 TTPs 1 IoCs

evasion

Modify Registry

Processes:

2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe

description	ioc	process
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\EnableLUA = "0"	2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe

C:\Users\Admin\AppData\Local\Temp\2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe
"C:\Users\Admin\AppData\Local\Temp\2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe"
1⤵
- UAC bypass
- Windows security bypass
- Checks computer location settings
- Windows security modification
- Checks whether UAC is enabled
- Suspicious use of SetThreadContext
- Suspicious use of WriteProcessMemory
- System policy modification
PID:3100

C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
"C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" Add-MpPreference -ExclusionPath "C:\Users\Admin\AppData\Local\Temp\2b4d871271fbc3f9487d370b9315bca0b9ca44ee81ecce6b89a57b31f7cf4598.exe" -Force
2⤵
- Command and Scripting Interpreter: PowerShell
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
PID:3076

C:\Windows\Microsoft.NET\Framework\v4.0.30319\msbuild.exe
"C:\Windows\Microsoft.NET\Framework\v4.0.30319\msbuild.exe"
2⤵
PID:840

C:\Windows\Microsoft.NET\Framework\v4.0.30319\installutil.exe
"C:\Windows\Microsoft.NET\Framework\v4.0.30319\installutil.exe"
2⤵
PID:3916

C:\Windows\Microsoft.NET\Framework\v4.0.30319\regasm.exe
"C:\Windows\Microsoft.NET\Framework\v4.0.30319\regasm.exe"
2⤵
- Adds Run key to start application
- Checks whether UAC is enabled
- Drops file in Program Files directory
- Suspicious behavior: EnumeratesProcesses
- Suspicious behavior: GetForegroundWindowSpam
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:208

C:\Windows\SysWOW64\schtasks.exe
"schtasks.exe" /create /f /tn "NAT Subsystem" /xml "C:\Users\Admin\AppData\Local\Temp\tmpE3A9.tmp"
3⤵
- Scheduled Task/Job: Scheduled Task
PID:1040

C:\Windows\SysWOW64\schtasks.exe
"schtasks.exe" /create /f /tn "NAT Subsystem Task" /xml "C:\Users\Admin\AppData\Local\Temp\tmpE485.tmp"
3⤵
- Scheduled Task/Job: Scheduled Task
PID:4620

C:\Windows\Microsoft.NET\Framework\v4.0.30319\regasm.exe
"C:\Windows\Microsoft.NET\Framework\v4.0.30319\regasm.exe"
2⤵
PID:3012

Network

MITRE ATT&CK Matrix ATT&CK v13

Initial Access

Execution

Command and Scripting Interpreter

T1059

PowerShell

T1059.001

Scheduled Task/Job

T1053

Scheduled Task

T1053.005

Persistence

Boot or Logon Autostart Execution

T1547

Registry Run Keys / Startup Folder

T1547.001

Scheduled Task/Job

T1053

Scheduled Task

T1053.005

Privilege Escalation

Abuse Elevation Control Mechanism

T1548

Bypass User Account Control

T1548.002

Boot or Logon Autostart Execution

T1547

Registry Run Keys / Startup Folder

T1547.001

Scheduled Task/Job

T1053

Scheduled Task

T1053.005

Defense Evasion

Abuse Elevation Control Mechanism

T1548

Bypass User Account Control

T1548.002

Impair Defenses

3

T1562

Disable or Modify Tools

Modify Registry

Credential Access

Discovery

Query Registry