autochk.exe

File Path: C:\Windows\SysWOW64\autochk.exe
Description: Auto Check Utility

Hashes

Type	Hash
MD5	`5FA6F24780340ECA9CC2F1E6184E5899`
SHA1	`7268650CB517A9534B4B6B2DDC5C1F231E6E90DC`
SHA256	`AB28506B58EC7C62D5BFAD4BB6EF754B490A28ABEF3D51C1C8E877468FB283CA`
SHA384	`DCB47945CBE944674B57C951BB8DB8547C9C887E7CFE500204B9ACBE0ECB58143E40A1B03A112166AAC12FC264B130CF`
SHA512	`8D401CB5A66ED6386587B73A26580ADE1CD04034078779C0D368E982AA0A016787978529E30FB3AA06A7E33308F85B180EDAFB93C111AC13877B5CFCA794A1E0`
SSDEEP	`24576:WkH2cxc0bLabLmNGwJEVW9IHUeyTxy3HNEPh0:WYreLyGwJEVLHzyg3HNEPh0`

Signature

Status: Signature verified.
Serial: 33000001C422B2F79B793DACB20000000001C4
Thumbprint: AE9C1AE54763822EEC42474983D8B635116C8452
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: AutoChk.Exe
Product Name: Microsoft Windows Operating System
Company Name: Microsoft Corporation
File Version: 10.0.17763.1 (WinBuild.160101.0800)
Product Version: 10.0.17763.1
Language: English (United States)
Legal Copyright: Microsoft Corporation. All rights reserved.

Possible Misuse

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

Source	Source File	Example	License
malware-ioc	misp_invisimole.json	"description": "Adding an entry to the \"run keys\" in the Registry or startup folder will cause the program referenced to be executed when a user logs in. (Citation: Microsoft Run Key) These programs will be executed under the context of the user and will have the account's associated permissions level.\n\nThe following run keys are created by default on Windows systems:\n* <code>HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\Run</code>\n* <code>HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\RunOnce</code>\n* <code>HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\Run</code>\n* <code>HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\RunOnce</code>\n\nThe <code>HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\RunOnceEx</code> is also available but is not created by default on Windows Vista and newer. Registry run key entries can reference programs directly or list them as a dependency. (Citation: Microsoft RunOnceEx APR 2018) For example, it is possible to load a DLL at logon using a \"Depend\" key with RunOnceEx: <code>reg add HKLM\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\RunOnceEx\\0001\\Depend /v 1 /d \"C:\\temp\\evil[.]dll\"</code> (Citation: Oddvar Moe RunOnceEx Mar 2018)\n\nThe following Registry keys can be used to set startup folder items for persistence:\n* <code>HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\Explorer\\User Shell Folders</code>\n* <code>HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\Explorer\\Shell Folders</code>\n* <code>HKEY_LOCAL_MACHINE\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Explorer\\Shell Folders</code>\n* <code>HKEY_LOCAL_MACHINE\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Explorer\\User Shell Folders</code>\n\nThe following Registry keys can control automatic startup of services during boot:\n* <code>HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\RunServicesOnce</code>\n* <code>HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\RunServicesOnce</code>\n* <code>HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\RunServices</code>\n* <code>HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\RunServices</code>\n\nUsing policy settings to specify startup programs creates corresponding values in either of two Registry keys:\n* <code>HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows\\CurrentVersion\\Policies\\Explorer\\Run</code>\n* <code>HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\Policies\\Explorer\\Run</code>\n\nThe Winlogon key controls actions that occur when a user logs on to a computer running Windows 7. Most of these actions are under the control of the operating system, but you can also add custom actions here. The <code>HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows NT\\CurrentVersion\\Winlogon\\Userinit</code> and <code>HKEY_LOCAL_MACHINE\\Software\\Microsoft\\Windows NT\\CurrentVersion\\Winlogon\\Shell</code> subkeys can automatically launch programs.\n\nPrograms listed in the load value of the registry key <code>HKEY_CURRENT_USER\\Software\\Microsoft\\Windows NT\\CurrentVersion\\Windows</code> run when any user logs on.\n\nBy default, the multistring BootExecute value of the registry key <code>HKEY_LOCAL_MACHINE\\System\\CurrentControlSet\\Control\\Session Manager</code> is set to autocheck autochk *. This value causes Windows, at startup, to check the file-system integrity of the hard disks if the system has been shut down abnormally. Adversaries can add other programs or processes to this registry value which will automatically launch at boot.\n\n\nAdversaries can use these configuration locations to execute malware, such as remote access tools, to maintain persistence through system reboots. Adversaries may also use [Masquerading](https://attack.mitre.org/techniques/T1036) to make the Registry entries look as if they are associated with legitimate programs.",	© ESET 2014-2018
atomic-red-team	T1547.001.md	By default, the multistring `BootExecute` value of the registry key `HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager` is set to `autocheck autochk *`. This value causes Windows, at startup, to check the file-system integrity of the hard disks if the system has been shut down abnormally. Adversaries can add other programs or processes to this registry value which will automatically launch at boot.	MIT License. © 2018 Red Canary

Additional Info*

*The information below is copied from MicrosoftDocs, which is maintained by Microsoft. Available under CC BY 4.0 license.

autochk

Runs when the computer is started and prior to Windows Server starting to verify the logical integrity of a file system.

Autochk.exe is a version of chkdsk that runs only on NTFS disks and only before Windows Server starts. autochk cannot be run directly from the command-line. Instead, autochk runs in the following situations:

If you try to run chkdsk on the boot volume.
If chkdsk cannot gain exclusive use of the volume.
If the volume is flagged as dirty.

Remarks

[!WARNING] The autochk command-line tool cannot be directly run from the command-line. Instead, use the chkntfs command-line tool to configure the way you want autochk to run at startup.

You can use chkntfs with the /x parameter to prevent autochk from running on a specific volume or multiple volumes.

Use the chkntfs.exe command-line tool with the /t parameter to change the autochk delay from 0 seconds to up to 3 days (259,200 seconds). However, a long delay means that the computer does not start until the time elapses or until you press a key to cancel autochk.