> 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/mailbox-client-access-setting-cas-changed.md).

# Mailbox Client Access Setting (CAS) changed

### Synopsis

| Field                | Value                                                                                                                         |
| -------------------- | ----------------------------------------------------------------------------------------------------------------------------- |
| Activation Period    | 14 Days                                                                                                                       |
| Training Period      | 30 Days                                                                                                                       |
| Test Period          | N/A (single event)                                                                                                            |
| Deduplication Period | 1 Day                                                                                                                         |
| Required Data        | <p>Requires one of the following data sources:<br>Windows Event Collector OR XDR Agent with eXtended Threat Hunting (XTH)</p> |
| ATT\&CK Tactic       | Collection (TA0009)                                                                                                           |
| ATT\&CK Technique    | Data Staged: Local Data Staging (T1074.001)                                                                                   |
| Severity             | Medium                                                                                                                        |

### Description

An attacker may use PowerShell to change the Client Access Settings (CAS) for a mailbox, hence gaining access to the data.

### Attacker's Goals

Gain access to the data in the compromised mailbox.

### Investigative actions

* Examine the PowerShell command to identify which mailbox's access setting has been modified.
* Verify that the change in the client access setting was executed by a trusted source.


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