sality | 639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c

Windows Service

T1543.003

Disable or Modify System Firewall

T1562.004

description	ioc	Process
Set value (int)	\REGISTRY\MACHINE\SYSTEM\ControlSet001\services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\EnableFirewall = "0"	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Set value (int)	\REGISTRY\MACHINE\SYSTEM\ControlSet001\services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\DoNotAllowExceptions = "0"	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Set value (int)	\REGISTRY\MACHINE\SYSTEM\ControlSet001\services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\DisableNotifications = "1"	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Set value (int)	\REGISTRY\MACHINE\SYSTEM\ControlSet001\services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\EnableFirewall = "0"	Au_.exe
Set value (int)	\REGISTRY\MACHINE\SYSTEM\ControlSet001\services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\DoNotAllowExceptions = "0"	Au_.exe
Set value (int)	\REGISTRY\MACHINE\SYSTEM\ControlSet001\services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\DisableNotifications = "1"	Au_.exe

Sality
Sality is backdoor written in C++, first discovered in 2003.
backdoor sality
Sality family
sality

UAC bypass 3 TTPs 2 IoCs

Bypass User Account Control

T1548.002

Disable or Modify Tools

Modify Registry

description	ioc	Process
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\EnableLUA = "0"	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\EnableLUA = "0"	Au_.exe

Windows security bypass 2 TTPs 12 IoCs

Disable or Modify Tools

Modify Registry

description	ioc	Process
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\FirewallDisableNotify = "1"	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\UpdatesDisableNotify = "1"	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\AntiVirusDisableNotify = "1"	Au_.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\FirewallDisableNotify = "1"	Au_.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\FirewallOverride = "1"	Au_.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\UpdatesDisableNotify = "1"	Au_.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\AntiVirusOverride = "1"	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\AntiVirusDisableNotify = "1"	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\FirewallOverride = "1"	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\UacDisableNotify = "1"	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\AntiVirusOverride = "1"	Au_.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\UacDisableNotify = "1"	Au_.exe

Deletes itself 1 IoCs

pid	Process
2660	Au_.exe

Executes dropped EXE 1 IoCs

pid	Process
2660	Au_.exe

Loads dropped DLL 3 IoCs

pid	Process
2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
2660	Au_.exe
2660	Au_.exe

Windows security modification 2 TTPs 14 IoCs

Disable or Modify Tools

Modify Registry

description	ioc	Process
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\AntiVirusOverride = "1"	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\FirewallDisableNotify = "1"	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\UacDisableNotify = "1"	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\AntiVirusOverride = "1"	Au_.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\FirewallOverride = "1"	Au_.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\UpdatesDisableNotify = "1"	Au_.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\UacDisableNotify = "1"	Au_.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\UpdatesDisableNotify = "1"	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\FirewallDisableNotify = "1"	Au_.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\AntiVirusDisableNotify = "1"	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\AntiVirusDisableNotify = "1"	Au_.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\FirewallOverride = "1"	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Key created	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\Svc	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Key created	\REGISTRY\MACHINE\SOFTWARE\Wow6432Node\Microsoft\Security Center\Svc	Au_.exe

Checks whether UAC is enabled 1 TTPs 2 IoCs

System Information Discovery

T1082

description	ioc	Process
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\EnableLUA = "0"	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\EnableLUA = "0"	Au_.exe

Enumerates connected drives 3 TTPs 14 IoCs

Attempts to read the root path of hard drives other than the default C: drive.

Query Registry

T1012

Peripheral Device Discovery

T1120

System Information Discovery

T1082

description	ioc	Process
File opened (read-only)	\??\H:	Au_.exe
File opened (read-only)	\??\J:	Au_.exe
File opened (read-only)	\??\L:	Au_.exe
File opened (read-only)	\??\O:	Au_.exe
File opened (read-only)	\??\M:	Au_.exe
File opened (read-only)	\??\P:	Au_.exe
File opened (read-only)	\??\E:	Au_.exe
File opened (read-only)	\??\I:	Au_.exe
File opened (read-only)	\??\K:	Au_.exe
File opened (read-only)	\??\N:	Au_.exe
File opened (read-only)	\??\Q:	Au_.exe
File opened (read-only)	\??\G:	Au_.exe
File opened (read-only)	\??\R:	Au_.exe
File opened (read-only)	\??\S:	Au_.exe

UPX packed file 26 IoCs

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

upx

resource	yara_rule
behavioral1/memory/2228-6-0x0000000001F00000-0x0000000002F8E000-memory.dmp	upx
behavioral1/memory/2228-3-0x0000000001F00000-0x0000000002F8E000-memory.dmp	upx
behavioral1/memory/2228-15-0x0000000001F00000-0x0000000002F8E000-memory.dmp	upx
behavioral1/memory/2228-9-0x0000000001F00000-0x0000000002F8E000-memory.dmp	upx
behavioral1/memory/2228-10-0x0000000001F00000-0x0000000002F8E000-memory.dmp	upx
behavioral1/memory/2228-7-0x0000000001F00000-0x0000000002F8E000-memory.dmp	upx
behavioral1/memory/2228-5-0x0000000001F00000-0x0000000002F8E000-memory.dmp	upx
behavioral1/memory/2228-4-0x0000000001F00000-0x0000000002F8E000-memory.dmp	upx
behavioral1/memory/2228-8-0x0000000001F00000-0x0000000002F8E000-memory.dmp	upx
behavioral1/memory/2228-50-0x0000000001F00000-0x0000000002F8E000-memory.dmp	upx
behavioral1/memory/2660-56-0x00000000021D0000-0x000000000325E000-memory.dmp	upx
behavioral1/memory/2660-59-0x00000000021D0000-0x000000000325E000-memory.dmp	upx
behavioral1/memory/2660-58-0x00000000021D0000-0x000000000325E000-memory.dmp	upx
behavioral1/memory/2660-57-0x00000000021D0000-0x000000000325E000-memory.dmp	upx
behavioral1/memory/2660-60-0x00000000021D0000-0x000000000325E000-memory.dmp	upx
behavioral1/memory/2660-61-0x00000000021D0000-0x000000000325E000-memory.dmp	upx
behavioral1/memory/2660-55-0x00000000021D0000-0x000000000325E000-memory.dmp	upx
behavioral1/memory/2660-54-0x00000000021D0000-0x000000000325E000-memory.dmp	upx
behavioral1/memory/2660-53-0x00000000021D0000-0x000000000325E000-memory.dmp	upx
behavioral1/memory/2660-151-0x00000000021D0000-0x000000000325E000-memory.dmp	upx
behavioral1/memory/2660-152-0x00000000021D0000-0x000000000325E000-memory.dmp	upx
behavioral1/memory/2660-195-0x00000000021D0000-0x000000000325E000-memory.dmp	upx
behavioral1/memory/2660-196-0x00000000021D0000-0x000000000325E000-memory.dmp	upx
behavioral1/memory/2660-197-0x00000000021D0000-0x000000000325E000-memory.dmp	upx
behavioral1/memory/2660-199-0x00000000021D0000-0x000000000325E000-memory.dmp	upx
behavioral1/memory/2660-200-0x00000000021D0000-0x000000000325E000-memory.dmp	upx

Drops file in Windows directory 1 IoCs

description	ioc	Process
File opened for modification	C:\Windows\SYSTEM.INI	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe

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 2 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	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Key opened	\REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language	Au_.exe

Suspicious behavior: EnumeratesProcesses 3 IoCs

pid	Process
2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
2660	Au_.exe
2660	Au_.exe

Suspicious use of AdjustPrivilegeToken 45 IoCs

description	pid	Process
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe
Token: SeDebugPrivilege	2660	Au_.exe

Suspicious use of WriteProcessMemory 19 IoCs

description	pid	Process	procid_target
PID 2228 wrote to memory of 1112	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe	19
PID 2228 wrote to memory of 1168	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe	20
PID 2228 wrote to memory of 1196	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe	21
PID 2228 wrote to memory of 1304	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe	23
PID 2228 wrote to memory of 2660	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe	30
PID 2228 wrote to memory of 2660	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe	30
PID 2228 wrote to memory of 2660	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe	30
PID 2228 wrote to memory of 2660	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe	30
PID 2228 wrote to memory of 2660	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe	30
PID 2228 wrote to memory of 2660	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe	30
PID 2228 wrote to memory of 2660	2228	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe	30
PID 2660 wrote to memory of 1112	2660	Au_.exe	19
PID 2660 wrote to memory of 1168	2660	Au_.exe	20
PID 2660 wrote to memory of 1196	2660	Au_.exe	21
PID 2660 wrote to memory of 1304	2660	Au_.exe	23
PID 2660 wrote to memory of 1112	2660	Au_.exe	19
PID 2660 wrote to memory of 1168	2660	Au_.exe	20
PID 2660 wrote to memory of 1196	2660	Au_.exe	21
PID 2660 wrote to memory of 1304	2660	Au_.exe	23

System policy modification 1 TTPs 2 IoCs

defense_evasion

Modify Registry

description	ioc	Process
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\EnableLUA = "0"	639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
Set value (int)	\REGISTRY\MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\EnableLUA = "0"	Au_.exe

C:\Windows\system32\taskhost.exe
"taskhost.exe"
1⤵
PID:1112

C:\Windows\system32\Dwm.exe
"C:\Windows\system32\Dwm.exe"
1⤵
PID:1168

C:\Windows\Explorer.EXE
C:\Windows\Explorer.EXE
1⤵
PID:1196
- C:\Users\Admin\AppData\Local\Temp\639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe
  "C:\Users\Admin\AppData\Local\Temp\639c5053b060176ae34d35d3d81a0d51d93d5ec06dce6c6a743e0e39ebe5303c.exe"
  2⤵
  - Modifies firewall policy service
  - UAC bypass
  - Windows security bypass
  - Loads dropped DLL
  - Windows security modification
  - Checks whether UAC is enabled
  - Drops file in Windows directory
  - System Location Discovery: System Language Discovery
  - Suspicious behavior: EnumeratesProcesses
  - Suspicious use of AdjustPrivilegeToken
  - Suspicious use of WriteProcessMemory
  - System policy modification
  PID:2228
- - C:\Users\Admin\AppData\Local\Temp\~nsu.tmp\Au_.exe
    "C:\Users\Admin\AppData\Local\Temp\~nsu.tmp\Au_.exe" _?=C:\Users\Admin\AppData\Local\Temp\
    3⤵
    - Modifies firewall policy service
    - UAC bypass
    - Windows security bypass
    - Deletes itself
    - Executes dropped EXE
    - Loads dropped DLL
    - Windows security modification
    - Checks whether UAC is enabled
    - Enumerates connected drives
    - System Location Discovery: System Language Discovery
    - Suspicious behavior: EnumeratesProcesses
    - Suspicious use of AdjustPrivilegeToken
    - Suspicious use of WriteProcessMemory
    - System policy modification
    PID:2660

C:\Windows\system32\DllHost.exe
C:\Windows\system32\DllHost.exe /Processid:{3EB3C877-1F16-487C-9050-104DBCD66683}
1⤵
PID:1304

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Persistence

Create or Modify System Process

T1543

Windows Service

T1543.003

Privilege Escalation

Abuse Elevation Control Mechanism

T1548

Bypass User Account Control

T1548.002

Create or Modify System Process

T1543

Windows Service

T1543.003

Defense Evasion

Abuse Elevation Control Mechanism

T1548

Bypass User Account Control

T1548.002

Impair Defenses

T1562

Disable or Modify System Firewall

T1562.004

Disable or Modify Tools

Modify Registry