> 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/first-seen-email-from-mailbox-owner-to-external-recipient-s-address-in-the-last-30-days.md).
# First-seen email from mailbox owner to external recipient's address in the last 30 days
### Synopsis
| Field | Value |
| -------------------- | ---------------------------------------------- |
| Activation Period | 14 Days |
| Training Period | 30 Days |
| Test Period | N/A (single event) |
| Deduplication Period | 1 Day |
| Required Data | Microsoft 365 Emails |
| Detection Modules | Email |
| Detector Tags | Exfiltration, Account Takeover |
| ATT\&CK Tactic | Exfiltration (TA0010) |
| ATT\&CK Technique | Exfiltration Over Alternative Protocol (T1048) |
| Severity | Informational |
### Description
Internal sender initiated first-time communication with an external recipient in the last 30 days.
### Attacker's Goals
* Extracting valuable information outside the company.
### Investigative actions
* Check the content of the email that was sent.
* Review the external recipient address and assess its reputation.
* Review past emails sent from this mailbox for any suspicious activity.
* Check for unusual emails sent to this recipient's address.
* Monitor further action taken, such as accessing to private keys, API tokens and sensitive data.
### Variations
First-time email to the disposable domain
**Synopsis**
| Field | Value |
| ----------------- | ---------------------------------------------- |
| ATT\&CK Tactic | Exfiltration (TA0010) |
| ATT\&CK Technique | Exfiltration Over Alternative Protocol (T1048) |
| Severity | Low |
**Description**
Internal sender emailed to external address(es) with disposable domain.
**Attacker's Goals**
* Extracting valuable information outside the company.
**Investigative actions**
* Check the content of the email that was sent.
* Review the external recipient address and assess its reputation.
* Review past emails sent from this mailbox for any suspicious activity.
* Check for unusual emails sent to this recipient's address.
* Monitor further action taken, such as accessing to private keys, API tokens and sensitive data.
First-time email from organization's domain with the external recipient's domain in the last 30 days
**Synopsis**
| Field | Value |
| ----------------- | ---------------------------------------------- |
| ATT\&CK Tactic | Exfiltration (TA0010) |
| ATT\&CK Technique | Exfiltration Over Alternative Protocol (T1048) |
| Severity | Informational |
**Description**
Internal sender emailed an external address belonging to a domain seen for the first time by the organization domain in the last 30 days.
**Attacker's Goals**
* Extracting valuable information outside the company.
**Investigative actions**
* Check the content of the email that was sent.
* Review the external recipient address and assess its reputation.
* Review past emails sent from this mailbox for any suspicious activity.
* Check for unusual emails sent to this recipient's address.
* Monitor further action taken, such as accessing to private keys, API tokens and sensitive data.
First-time email from organization with the external recipient in the last 30 days
**Synopsis**
| Field | Value |
| ----------------- | ---------------------------------------------- |
| ATT\&CK Tactic | Exfiltration (TA0010) |
| ATT\&CK Technique | Exfiltration Over Alternative Protocol (T1048) |
| Severity | Informational |
**Description**
Internal sender emailed to external address(es) that first-seen by the the whole organization in the last 30 days.
**Attacker's Goals**
* Extracting valuable information outside the company.
**Investigative actions**
* Check the content of the email that was sent.
* Review the external recipient address and assess its reputation.
* Review past emails sent from this mailbox for any suspicious activity.
* Check for unusual emails sent to this recipient's address.
* Monitor further action taken, such as accessing to private keys, API tokens and sensitive data.
First-time email from organization's domain to the external recipient in the last 30 days
**Synopsis**
| Field | Value |
| ----------------- | ---------------------------------------------- |
| ATT\&CK Tactic | Exfiltration (TA0010) |
| ATT\&CK Technique | Exfiltration Over Alternative Protocol (T1048) |
| Severity | Informational |
**Description**
Internal sender emailed to external address(es) that first-seen by the organization domain in the last 30 days.
**Attacker's Goals**
* Extracting valuable information outside the company.
**Investigative actions**
* Check the content of the email that was sent.
* Review the external recipient address and assess its reputation.
* Review past emails sent from this mailbox for any suspicious activity.
* Check for unusual emails sent to this recipient's address.
* Monitor further action taken, such as accessing to private keys, API tokens and sensitive data.
First-time email from mailbox owner to the external recipient's domain in the last 30 days
**Synopsis**
| Field | Value |
| ----------------- | ---------------------------------------------- |
| ATT\&CK Tactic | Exfiltration (TA0010) |
| ATT\&CK Technique | Exfiltration Over Alternative Protocol (T1048) |
| Severity | Informational |
**Description**
Internal sender emailed to external address(es) with domain that first-seen by that sender in the last 30 days.
**Attacker's Goals**
* Extracting valuable information outside the company.
**Investigative actions**
* Check the content of the email that was sent.
* Review the external recipient address and assess its reputation.
* Review past emails sent from this mailbox for any suspicious activity.
* Check for unusual emails sent to this recipient's address.
* Monitor further action taken, such as accessing to private keys, API tokens and sensitive data.
First-time outbound email from mailbox owner to multiple external recipients without any internal recipients in the last 30 days
**Synopsis**
| Field | Value |
| ----------------- | ---------------------------------------------- |
| ATT\&CK Tactic | Exfiltration (TA0010) |
| ATT\&CK Technique | Exfiltration Over Alternative Protocol (T1048) |
| Severity | Informational |
**Description**
Internal sender emailed first-time to multiple external recipients with no internal recipients included in the last 30 days.
**Attacker's Goals**
* Extracting valuable information outside the company.
**Investigative actions**
* Check the content of the email that was sent.
* Review the external recipient address and assess its reputation.
* Review past emails sent from this mailbox for any suspicious activity.
* Check for unusual emails sent to this recipient's address.
* Monitor further action taken, such as accessing to private keys, API tokens and sensitive data.
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