Detection rules › Splunk

Windows Firewall Rule Modification

Author
Teoderick Contreras, Splunk
Source
upstream

This detection identifies instances where a Windows Firewall rule has been modified, which may indicate an attempt to alter security policies. Unauthorized modifications can weaken firewall protections, allowing malicious traffic or preventing legitimate communications. The event logs details such as the modified rule name, protocol, ports, application path, and the user responsible for the change. Security teams should monitor unexpected modifications, correlate them with related events, and investigate anomalies to prevent unauthorized access and maintain network security integrity.

MITRE ATT&CK coverage

TacticTechniques
Defense EvasionT1562.004 Impair Defenses: Disable or Modify System Firewall

Event coverage

ProviderEvent IDTitle
Security-Auditing4947A change has been made to Windows Firewall exception list. A rule was modified.

Stages and Predicates

Stage 1: search

search EventCode=4947

Stage 2: stats

stats BY RuleName, signature, subject, status, dest, ProcessID

Stage 3: search

search

Stage 4: search

search

Stage 5: search

search `macro`

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.

FieldKindValues
EventCodeeq
  • 4947