A Rule Has Been Deleted From The Windows Firewall Exception List

Severity: medium
Author: frack113
Source: upstream

Detects when a single rules or all of the rules have been deleted from the Windows Defender Firewall

MITRE ATT&CK coverage

Tactic	Techniques
Defense Evasion	`T1562.004` Impair Defenses: Disable or Modify System Firewall

Event coverage

Provider	Event ID	Title
Windows-Firewall-With-Advanced-Security	2006
Windows-Firewall-With-Advanced-Security	2052

Stages and Predicates

Stage 1: `selection`

Stage 2: `not 1 of filter_main_*`

or:
ModifyingApplication: ''
ModifyingApplication: 'C:\Windows\System32\svchost.exe'
ModifyingApplication: null
ModifyingApplication|startswith: 'C:\Program Files (x86)\'
ModifyingApplication|startswith: 'C:\Program Files\'
ModifyingApplication|startswith: 'C:\Windows\WinSxS\'

Stage 3: `not 1 of filter_optional_msmpeng`

ModifyingApplication|endswith: '\MsMpEng.exe'
ModifyingApplication|startswith: 'C:\ProgramData\Microsoft\Windows Defender\Platform\'

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

Field	Kind	Values
`ModifyingApplication`	ends_with	`\MsMpEng.exe` corpus 2 (sigma 2)
`ModifyingApplication`	eq	`C:\Windows\System32\svchost.exe` corpus 2 (sigma 2)
`ModifyingApplication`	starts_with	`C:\Program Files (x86)\` `C:\Program Files\` `C:\ProgramData\Microsoft\Windows Defender\Platform\` corpus 2 (sigma 2) `C:\Windows\WinSxS\` corpus 2 (sigma 2)