> 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/outbound-email-contains-file-sharing-service-link-sent-to-external-recipient.md).

# Outbound email contains file-sharing service link sent to external recipient

### Synopsis

| Field                | Value                                                              |
| -------------------- | ------------------------------------------------------------------ |
| Activation Period    | 14 Days                                                            |
| Training Period      | 30 Days                                                            |
| Test Period          | N/A (single event)                                                 |
| Deduplication Period | 1 Hour 30 Minutes                                                  |
| Required Data        | Microsoft 365 Emails                                               |
| Detection Modules    | Email                                                              |
| Detector Tags        | Exfiltration                                                       |
| ATT\&CK Tactic       | Execution (TA0002), Credential Access (TA0006)                     |
| ATT\&CK Technique    | User Execution (T1204), Brute Force: Password Cracking (T1110.002) |
| Severity             | Informational                                                      |

### Description

Identifies outbound emails that include links to file-sharing services sent externally.

### Attacker's Goals

Exfiltrate data by sharing a link to a file-sharing service with external recipients, bypassing attachment inspection and potentially evading visibility controls.

### Investigative actions

* Review the shared URL to determine if the file is publicly accessible or shared outside the organization.
* Check if the file-sharing domain has been previously used by this sender or others in the organization.
* Investigate recent outbound emails for similar use of file-sharing services or unusual external recipients.

### Variations

<details>

<summary>Outbound email to external recipient(s) uses first-seen for organization file-sharing service</summary>

**Synopsis**

| Field             | Value                                                              |
| ----------------- | ------------------------------------------------------------------ |
| ATT\&CK Tactic    | Execution (TA0002), Credential Access (TA0006)                     |
| ATT\&CK Technique | User Execution (T1204), Brute Force: Password Cracking (T1110.002) |
| Severity          | Informational                                                      |

**Description**

Identifies outbound emails that include links to file-sharing services sent externally.

**Attacker's Goals**

Exfiltrate data by sharing a link to a file-sharing service with external recipients, bypassing attachment inspection and potentially evading visibility controls.

**Investigative actions**

* Review the shared URL to determine if the file is publicly accessible or shared outside the organization.
* Check if the file-sharing domain has been previously used by this sender or others in the organization.
* Investigate recent outbound emails for similar use of file-sharing services or unusual external recipients.

</details>

<details>

<summary>Outbound email to external recipient(s) uses first-seen for sender file-sharing service</summary>

**Synopsis**

| Field             | Value                                                              |
| ----------------- | ------------------------------------------------------------------ |
| ATT\&CK Tactic    | Execution (TA0002), Credential Access (TA0006)                     |
| ATT\&CK Technique | User Execution (T1204), Brute Force: Password Cracking (T1110.002) |
| Severity          | Informational                                                      |

**Description**

Identifies outbound emails that include links to file-sharing services sent externally.

**Attacker's Goals**

Exfiltrate data by sharing a link to a file-sharing service with external recipients, bypassing attachment inspection and potentially evading visibility controls.

**Investigative actions**

* Review the shared URL to determine if the file is publicly accessible or shared outside the organization.
* Check if the file-sharing domain has been previously used by this sender or others in the organization.
* Investigate recent outbound emails for similar use of file-sharing services or unusual external recipients.

</details>


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://cortex-docs.paloaltonetworks.com/analytics-alerts/alerts-by-name/outbound-email-contains-file-sharing-service-link-sent-to-external-recipient.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.