> 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/email-attachment-with-right-to-left-override-unicode-character.md).

# Email attachment with Right-to-Left Override Unicode character

### 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        | Evasion                                                                |
| ATT\&CK Tactic       | Stealth (TA0005), Execution (TA0002)                                   |
| ATT\&CK Technique    | Masquerading: Masquerade File Type (T1036.008), User Execution (T1204) |
| Severity             | Low                                                                    |

### Description

The email message contains an attachment with a hidden Right-to-Left Override Unicode character.

### Attacker's Goals

* Bypass security filters and deliver malicious content to users
* Mislead recipients into opening a malicious file by obscuring its true nature
* Deploy malicious attachments through emails to compromise systems, gain unauthorized access, or facilitate cyber threats.

### Investigative actions

* Carefully analyze attachments for any indications of suspicious or malicious behavior.
* Scrutinize the attachments for any suspicious indications.
* Confirm whether the attachments were successfully delivered to the recipient's mailbox.
* If the attachments were delivered successfully, verify whether the recipient downloaded them.


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