2019-03-11 13:48:16 -07:00

103 lines
6.7 KiB
Markdown

---
title: Configure how attack surface reduction rules work to finetune protection in your network
description: You can individually set rules in audit, block, or disabled modes, and add files and folders that should be excluded from ASR
keywords: Attack surface reduction, hips, host intrusion prevention system, protection rules, anti-exploit, antiexploit, exploit, infection prevention, customize, configure, exclude
search.product: eADQiWindows 10XVcnh
ms.pagetype: security
ms.prod: w10
ms.mktglfcycl: manage
ms.sitesec: library
ms.pagetype: security
ms.localizationpriority: medium
author: andreabichsel
ms.author: v-anbic
ms.date: 12/19/2018
---
# Customize attack surface reduction rules
**Applies to:**
- [Windows Defender Advanced Threat Protection (Windows Defender ATP)](https://go.microsoft.com/fwlink/p/?linkid=2069559)
Attack surface reduction rules help prevent actions and apps that are typically used by exploit-seeking malware to infect machines. Attack surface reduction rules are supported on Windows Server 2019 as well as Windows 10 clients.
This topic describes how to customize attack surface reduction rules by [excluding files and folders](#exclude-files-and-folders) or [adding custom text to the notification](#customize-the-notification) alert that appears on a user's computer.
You can use Group Policy, PowerShell, and MDM CSPs to configure these settings.
## Exclude files and folders
You can exclude files and folders from being evaluated by all attack surface reduction rules. This means that even if the file or folder contains malicious behavior as determined by an attack surface reduction rule, the file will not be blocked from running.
This could potentially allow unsafe files to run and infect your devices.
>[!WARNING]
>Excluding files or folders can severely reduce the protection provided by attack surface reduction rules. Files that would have been blocked by a rule will be allowed to run, and there will be no report or event recorded.
>
>If you are encountering problems with rules detecting files that you believe should not be detected, you should [use audit mode first to test the rule](enable-attack-surface-reduction.md#enable-and-audit-attack-surface-reduction-rules).
You can specify individual files or folders (using folder paths or fully qualified resource names) but you cannot specify if the exclusions should only be applied to individual rules: the exclusions will apply to all rules that are enabled (or placed in audit mode) and that allow exclusions.
Attack surface reduction supports environment variables and wildcards. For information about using wildcards, see [Use wildcards in the file name and folder path or extension exclusion lists](https://docs.microsoft.com/windows/security/threat-protection/windows-defender-antivirus/configure-extension-file-exclusions-windows-defender-antivirus#use-wildcards-in-the-file-name-and-folder-path-or-extension-exclusion-lists).
Exclusions apply to all attack surface reduction rules.
Rule description | GUID
-|:-:|-
Block all Office applications from creating child processes | D4F940AB-401B-4EFC-AADC-AD5F3C50688A
Block execution of potentially obfuscated scripts | 5BEB7EFE-FD9A-4556-801D-275E5FFC04CC
Block Win32 API calls from Office macro | 92E97FA1-2EDF-4476-BDD6-9DD0B4DDDC7B
Block Office applications from creating executable content | 3B576869-A4EC-4529-8536-B80A7769E899
Block Office applications from injecting code into other processes | 75668C1F-73B5-4CF0-BB93-3ECF5CB7CC84
Block JavaScript or VBScript from launching downloaded executable content | D3E037E1-3EB8-44C8-A917-57927947596D
Block executable content from email client and webmail | BE9BA2D9-53EA-4CDC-84E5-9B1EEEE46550
Block executable files from running unless they meet a prevalence, age, or trusted list criteria | 01443614-cd74-433a-b99e-2ecdc07bfc25
Use advanced protection against ransomware | c1db55ab-c21a-4637-bb3f-a12568109d35
Block credential stealing from the Windows local security authority subsystem (lsass.exe) | 9e6c4e1f-7d60-472f-ba1a-a39ef669e4b2
Block process creations originating from PSExec and WMI commands | d1e49aac-8f56-4280-b9ba-993a6d77406c
Block untrusted and unsigned processes that run from USB | b2b3f03d-6a65-4f7b-a9c7-1c7ef74a9ba4
Block Office communication applications from creating child processes | 26190899-1602-49e8-8b27-eb1d0a1ce869
Block Adobe Reader from creating child processes | 7674ba52-37eb-4a4f-a9a1-f0f9a1619a2c
See the [attack surface reduction](attack-surface-reduction-exploit-guard.md) topic for details on each rule.
### Use Group Policy to exclude files and folders
1. On your Group Policy management computer, open the [Group Policy Management Console](https://technet.microsoft.com/library/cc731212.aspx), right-click the Group Policy Object you want to configure and click **Edit**.
2. In the **Group Policy Management Editor** go to **Computer configuration** and click **Administrative templates**.
3. Expand the tree to **Windows components > Windows Defender Antivirus > Windows Defender Exploit Guard > Attack surface reduction**.
4. Double-click the **Exclude files and paths from Attack surface reduction Rules** setting and set the option to **Enabled**. Click **Show** and enter each file or folder in the **Value name** column. Enter **0** in the **Value** column for each item.
### Use PowerShell to exclude files and folderss
1. Type **powershell** in the Start menu, right click **Windows PowerShell** and click **Run as administrator**
2. Enter the following cmdlet:
```PowerShell
Add-MpPreference -AttackSurfaceReductionOnlyExclusions "<fully qualified path or resource>"
```
Continue to use `Add-MpPreference -AttackSurfaceReductionOnlyExclusions` to add more folders to the list.
>[!IMPORTANT]
>Use `Add-MpPreference` to append or add apps to the list. Using the `Set-MpPreference` cmdlet will overwrite the existing list.
### Use MDM CSPs to exclude files and folders
Use the [./Vendor/MSFT/Policy/Config/Defender/AttackSurfaceReductionOnlyExclusions](https://docs.microsoft.com/windows/client-management/mdm/policy-csp-defender#defender-attacksurfacereductiononlyexclusions) configuration service provider (CSP) to add exclusions.
## Customize the notification
See the [Windows Security](../windows-defender-security-center/windows-defender-security-center.md#customize-notifications-from-the-windows-defender-security-center) topic for more information about customizing the notification when a rule is triggered and blocks an app or file.
## Related topics
- [Reduce attack surfaces with attack surface reduction rules](attack-surface-reduction-exploit-guard.md)
- [Enable attack surface reduction rules](enable-attack-surface-reduction.md)
- [Evaluate attack surface reduction rules](evaluate-attack-surface-reduction.md)