> For the complete documentation index, see [llms.txt](https://cortex-docs.paloaltonetworks.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://cortex-docs.paloaltonetworks.com/analytics-alerts/alerts-by-name/a-user-added-a-windows-firewall-rule.md).

# A user added a Windows firewall rule

### Synopsis

| Field                | Value                                                          |
| -------------------- | -------------------------------------------------------------- |
| Activation Period    | 14 Days                                                        |
| Training Period      | 30 Days                                                        |
| Test Period          | N/A (single event)                                             |
| Deduplication Period | 1 Day                                                          |
| Required Data        | XDR Agent with eXtended Threat Hunting (XTH)                   |
| Detection Modules    | Identity Threat Module                                         |
| ATT\&CK Tactic       | Defense Evasion (TA0005)                                       |
| ATT\&CK Technique    | Impair Defenses: Disable or Modify System Firewall (T1562.004) |
| Severity             | Informational                                                  |

### Description

A user added a new Windows Firewall rule. Adding a firewall rule may indicate an attempt to bypass controls limiting network usage or to disrupt network communications.

### Attacker's Goals

Firewall rules determine what traffic your firewall will block or allow. A malicious insider might want to change these rules in an attempt to bypass network limitations or disrupt network communication.

### Investigative actions

* Check for any other suspicious activity related to the host and the user involved in the alert.
* Check Windows Defender Firewall with Advanced Security for a new rule that was added.
* Check if the new rule was added to different machines as well.


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