> 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/rare-smtp-s-session.md).

# Rare SMTP/S Session

### 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>Palo Alto Networks Firewall traffic Logs OR XDR Agent OR Third-Party Firewalls</p> |
| ATT\&CK Tactic       | Exfiltration (TA0010)                                                                                                                |
| ATT\&CK Technique    | Exfiltration Over Alternative Protocol (T1048)                                                                                       |
| Severity             | Informational                                                                                                                        |

### Description

The Simple Mail Transfer Protocol (SMTP) and its SSL-secured variant SMTPS are used to send email. Attackers can use SMTP/S to exfiltrate data from your network.

### Attacker's Goals

SMTP and its SSL-secured variant SMTPS are used to send email. Attackers can use SMTP/S to exfiltrate data from your network.

### Investigative actions

* Check whether the initiator process is benign or normal for the host and/or user performing it.
* Check whether additional malicious commands were executed from the same process.


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