EventID 2006: Firewall Rule Deleted

This event indicates that a firewall rule has been deleted.

In recent builds of Windows 11, this event has been replaced by a new Event ID:

EventID 2052: Firewall Rule Deleted

Analysis Value

Security IdentifierFile PathExecution AccountParent and Child InformationEvidence of ExecutionFirewall Activity

Operating System Availability

Major Version	Support	Major Version	Support
Windows 11	⚠️	Server 2019	✅
Windows 10	✅	Server 2016	✅
Windows 8	✅	Server 2012	✅
Windows 7	✅	Server 2008	✅
Windows Vista	✅	Server 2003	❌
Windows XP	❌

Artifact Location(s)

• %SystemRoot%\System32\Winevt\Logs\Microsoft-Windows-Windows Firewall With Advanced Security%4Firewall.evtx

Artifact Interpretation

Field	Interpretation	Reference
System/Security/UserID	Provides the Security Identifier (SID) of the account that deleted the firewall rule.	Security Identifier
EventData/ModifyingUser	Provides the Security Identifier (SID) of the account that deleted the firewall rule.	Security Identifier
EventData/ModifyingApplication	Provides the full image path of the process that deleted the firewall rule.	File Path
System/Execution/ProcessID	Provides the Process ID of the application that deleted the firewall rule.	Parent and Child Information
System/Execution/ThreadID	Provides the Thread ID of the application that deleted the firewall rule.	Parent and Child Information

The presence of this event indicates that the system's firewall was modified by deleting a rule. This may be indicative of attacker activity. There are many legitimate processes such as svchost.exe that will be observed modifying the Windows Firewall, so this event should be correlated with others to determine if the activity is legitimate or not.

The following additional fields are available in this event:

XML Path	Interpretation
EventData/RuleId	The GUID of the deleted firewall rule
EventData/RuleName	The name for the deleted firewall rule as it appeared in the Windows Firewall

Example - Windows 10

On an example system, an existing Windows Firewall rule was deleted from within the Windows Defender Firewall with Advanced Security control panel, causing the following event to be logged:

- 
<Event
	xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
-   <System>
		<Provider Name="Microsoft-Windows-Windows Firewall With Advanced Security" Guid="{d1bc9aff-2abf-4d71-9146-ecb2a986eb85}" />
		<EventID>2006</EventID>
		<Version>0</Version>
		<Level>4</Level>
		<Task>0</Task>
		<Opcode>0</Opcode>
		<Keywords>0x8000020000000000</Keywords>
		<TimeCreated SystemTime="2023-05-04T17:26:06.0482710Z" />
		<EventRecordID>6669</EventRecordID>
		<Correlation />
		<Execution ProcessID="2352" ThreadID="18980" />
		<Channel>Microsoft-Windows-Windows Firewall With Advanced Security/Firewall</Channel>
		<Computer>HLPC01</Computer>
		<Security UserID="S-1-5-19" />
	</System>
-   <EventData>
		<Data Name="RuleId">{8736B31E-8792-452E-8D2D-C45621F236AF}</Data>
		<Data Name="RuleName">Open SSH Port 22</Data>
		<Data Name="ModifyingUser">S-1-5-21-3471133136-2963561160-3931775028-1001</Data>
		<Data Name="ModifyingApplication">C:\Windows\System32\mmc.exe</Data>
	</EventData>
</Event>

This example was produced on Windows 10, Version 10.0.19044 Build 19044

Example - Windows 11

The same activity, when reproduced on a Windows 11 system, results in the following event being logged:

- 
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
-   <System>
		<Provider Name="Microsoft-Windows-Windows Firewall With Advanced Security" Guid="{d1bc9aff-2abf-4d71-9146-ecb2a986eb85}" />
		<EventID>2052</EventID>
		<Version>0</Version>
		<Level>4</Level>
		<Task>0</Task>
		<Opcode>0</Opcode>
		<Keywords>0x8000020000000000</Keywords>
		<TimeCreated SystemTime="2023-09-27T01:10:00.0598218Z" />
		<EventRecordID>552</EventRecordID>
		<Correlation />
		<Execution ProcessID="2704" ThreadID="3292" />
		<Channel>Microsoft-Windows-Windows Firewall With Advanced Security/Firewall</Channel>
		<Computer>W11</Computer>
		<Security UserID="S-1-5-19" />
	</System>
-   <EventData>
		<Data Name="RuleId">{0D458E97-4EC5-4C5C-A5A4-F9F73E769168}</Data>
		<Data Name="RuleName">Open SSH Port 22</Data>
		<Data Name="ModifyingUser">S-1-5-21-937911350-1118943250-2293061635-1001</Data>
		<Data Name="ModifyingApplication">C:\Windows\System32\mmc.exe</Data>
		<Data Name="ErrorCode">0</Data>
	</EventData>
</Event>

This example was produced on Windows 11, Version 10.0.22621 Build 22621