> 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/gcp-firewall-rule-modification.md).

# GCP Firewall Rule Modification

### Synopsis

| Field                | Value                                                         |
| -------------------- | ------------------------------------------------------------- |
| Activation Period    | 14 Days                                                       |
| Training Period      | 30 Days                                                       |
| Test Period          | N/A (single event)                                            |
| Deduplication Period | 3 Hours                                                       |
| Required Data        | Gcp Audit Log                                                 |
| Detection Modules    | Cloud                                                         |
| ATT\&CK Tactic       | Defense Impairment (TA0112)                                   |
| ATT\&CK Technique    | Disable or Modify System Firewall: Cloud Firewall (T1686.001) |
| Severity             | Informational                                                 |

### Description

A GCP firewall rule was modified. An attacker might use this technique to access restricted resources.

### Attacker's Goals

Access restricted resources.

### Investigative actions

* Check if there were any network attempts that fit the deleted rule.
* Check The cloud identity activity prior/after to the rule deletion.


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