wuauclt.exe

File Path: C:\Windows\system32\wuauclt.exe
Description: Windows Update

Hashes

Type	Hash
MD5	`95E303BF80AECA5A296E519C61F42427`
SHA1	`B523E0CD46B3E5F6CDCD6F99E8CC9932D9585B9E`
SHA256	`AC52D02086B83A2FA92E305E1EACD490101D08BE6C47210989BAA192E030DC06`
SHA384	`9C899FC7C606C6A2B9BF926510CBE2A902F82DAE7496BEBF83A844C066107C44BE2F01D8CBEF3B8F6952D63F4F3E5FEB`
SHA512	`884A18F68FE328958AD7B0EBA5A13515C517992423CF123DC81D44D0EAC5988771F7958D877997E9BFCA74427F99E2B87EFBCA8A44132164A6928E0368D3F125`
SSDEEP	`1536:HK0TzC8tY6HAqCsd56ncymh7TpkwsZYm+P/:HKE+8tY6H/FPRkLYm+n`

Runtime Data

Loaded Modules:

Path
C:\Windows\System32\combase.dll
C:\Windows\System32\KERNEL32.DLL
C:\Windows\System32\KERNELBASE.dll
C:\Windows\SYSTEM32\ntdll.dll
C:\Windows\System32\RPCRT4.dll
C:\Windows\System32\ucrtbase.dll
C:\Windows\system32\wuauclt.exe

Signature

Status: Signature verified.
Serial: 3300000266BD1580EFA75CD6D3000000000266
Thumbprint: A4341B9FD50FB9964283220A36A1EF6F6FAA7840
Issuer: CN=Microsoft Windows Production PCA 2011, O=Microsoft Corporation, L=Redmond, S=Washington, C=US
Subject: CN=Microsoft Windows, O=Microsoft Corporation, L=Redmond, S=Washington, C=US

File Metadata

Original Filename: wuauclt.exe
Product Name: Microsoft Windows Operating System
Company Name: Microsoft Corporation
File Version: 10.0.19041.423 (WinBuild.160101.0800)
Product Version: 10.0.19041.423
Language: Language Neutral
Legal Copyright: Microsoft Corporation. All rights reserved.

File Similarity (ssdeep match)

File	Score
C:\Windows\system32\wuauclt.exe	88
C:\Windows\system32\wuauclt.exe	68
C:\Windows\system32\wuauclt.exe	68
C:\Windows\system32\wuauclt.exe	90

Possible Misuse

The following table contains possible examples of wuauclt.exe being misused. While wuauclt.exe is not inherently malicious, its legitimate functionality can be abused for malicious purposes.

Source	Source File	Example	License
sigma	net_connection_win_wuauclt_network_connection.yml	`title: Wuauclt Network Connection`	DRL 1.0
sigma	net_connection_win_wuauclt_network_connection.yml	`description: Detects the use of the Windows Update Client binary (wuauclt.exe) to proxy execute code and making a network connections. One could easily make the DLL spawn a new process and inject to it to proxy the network connection and bypass this rule.`	DRL 1.0
sigma	net_connection_win_wuauclt_network_connection.yml	`- https://dtm.uk/wuauclt/`	DRL 1.0
sigma	net_connection_win_wuauclt_network_connection.yml	`Image\\|contains: wuauclt`	DRL 1.0
sigma	net_connection_win_wuauclt_network_connection.yml	`- Legitimate use of wuauclt.exe over the network.`	DRL 1.0
sigma	proc_creation_win_lolbas_execution_of_wuauclt.yml	`title: Monitoring Wuauclt.exe For Lolbas Execution Of DLL`	DRL 1.0
sigma	proc_creation_win_lolbas_execution_of_wuauclt.yml	`description: Adversaries can abuse wuauclt.exe (Windows Update client) to run code execution by specifying an arbitrary DLL.`	DRL 1.0
sigma	proc_creation_win_lolbas_execution_of_wuauclt.yml	`- https://dtm.uk/wuauclt/`	DRL 1.0
sigma	proc_creation_win_lolbas_execution_of_wuauclt.yml	`CommandLine\\|re: '(?i)wuauclt\.exe.\/UpdateDeploymentProvider.\/Runhandlercomserver'`	DRL 1.0
sigma	proc_creation_win_proxy_execution_wuauclt.yml	`title: Proxy Execution via Wuauclt`	DRL 1.0
sigma	proc_creation_win_proxy_execution_wuauclt.yml	`description: Detects the use of the Windows Update Client binary (wuauclt.exe) to proxy execute code.`	DRL 1.0
sigma	proc_creation_win_proxy_execution_wuauclt.yml	`- https://dtm.uk/wuauclt/`	DRL 1.0
sigma	proc_creation_win_proxy_execution_wuauclt.yml	`- Image\\|contains: wuauclt`	DRL 1.0
sigma	proc_creation_win_proxy_execution_wuauclt.yml	`- OriginalFileName: wuauclt.exe`	DRL 1.0
sigma	proc_creation_win_susp_spoolsv_child_processes.yml	`- \wuauclt.exe`	DRL 1.0
sigma	proc_creation_win_susp_wuauclt.yml	`description: Detects code execution via the Windows Update client (wuauclt)`	DRL 1.0
sigma	proc_creation_win_susp_wuauclt.yml	`- https://dtm.uk/wuauclt/`	DRL 1.0
sigma	proc_creation_win_susp_wuauclt.yml	`- '\wuauclt.exe'`	DRL 1.0
sigma	proc_creation_win_susp_wuauclt_cmdline.yml	`description: Detects suspicious Windows Update Agent activity in which a wuauclt.exe process command line doesn't contain any command line flags`	DRL 1.0
sigma	proc_creation_win_susp_wuauclt_cmdline.yml	`Image\\|endswith: '\Wuauclt.exe'`	DRL 1.0
sigma	proc_creation_win_susp_wuauclt_cmdline.yml	`CommandLine\\|endswith: '\Wuauclt.exe'`	DRL 1.0
sigma	registry_event_persistence_search_order.yml	`- C:\WINDOWS\system32\wuauclt.exe`	DRL 1.0
LOLBAS	Wuauclt.yml	`Name: wuauclt.exe`
LOLBAS	Wuauclt.yml	`- Command: wuauclt.exe /UpdateDeploymentProvider Full_Path_To_DLL /RunHandlerComServer`
LOLBAS	Wuauclt.yml	`- Path: C:\Windows\System32\wuauclt.exe`
LOLBAS	Wuauclt.yml	`- IOC: wuauclt run with a parameter of a DLL path`
LOLBAS	Wuauclt.yml	`- IOC: Suspicious wuauclt Internet/network connections`
LOLBAS	Wuauclt.yml	`- Link: https://dtm.uk/wuauclt/`
signature-base	apt_putterpanda.yar	$x0 = “WUAUCLT.EXE” fullword wide /* PEStudio Blacklist: strings / / score: ‘20.01’ */	CC BY-NC 4.0