> 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/possible-multistage-attack-in-microsoft-teams.md).

# Possible multistage attack in Microsoft Teams

### Synopsis

| Field                | Value                   |
| -------------------- | ----------------------- |
| Activation Period    | 14 Days                 |
| Training Period      | 30 Days                 |
| Test Period          | 12 Hours                |
| Deduplication Period | 1 Day                   |
| Required Data        | Office 365 Audit        |
| Detection Modules    | Identity Threat Module  |
| Detector Tags        | Microsoft Teams         |
| ATT\&CK Tactic       | Initial Access (TA0001) |
| ATT\&CK Technique    | Phishing (T1566)        |
| Severity             | Low                     |

### Description

Possible multistage attack in Microsoft Teams.

### Attacker's Goals

Attackers may leverage Microsoft Teams to conduct phishing attacks by exploiting trusted communication channels with users inside the organization.

### Investigative actions

* Verify the suspicious activity to validate the legitimacy of the user's actions.
* Review Teams chat logs and meeting invites for interactions with external tenants, focusing on unusual file sharing or unsolicited links.
* Hunt for known phishing indicators (suspicious domains, URL patterns, or IPs) in the Teams messages and linked content.
* Evaluate the external tenant reputation.
* Check for anomalous MS Teams actions like suspicious application installation, message extraction, policy changes or internal spear phishing attempts linked to the user post-login.
* Follow further actions done by the account.

### Variations

<details>

<summary>Malicious activity had been detected with strong indicators</summary>

**Synopsis**

| Field             | Value                   |
| ----------------- | ----------------------- |
| ATT\&CK Tactic    | Initial Access (TA0001) |
| ATT\&CK Technique | Phishing (T1566)        |
| Severity          | Medium                  |

**Description**

Malicious Microsoft Teams activity detected across multiple indicators, the activities have strong indications of a malicious action.

**Attacker's Goals**

Attackers may leverage Microsoft Teams to conduct phishing attacks by exploiting trusted communication channels with users inside the organization.

**Investigative actions**

* Verify the suspicious activity to validate the legitimacy of the user's actions.
* Review Teams chat logs and meeting invites for interactions with external tenants, focusing on unusual file sharing or unsolicited links.
* Hunt for known phishing indicators (suspicious domains, URL patterns, or IPs) in the Teams messages and linked content.
* Evaluate the external tenant reputation.
* Check for anomalous MS Teams actions like suspicious application installation, message extraction, policy changes or internal spear phishing attempts linked to the user post-login.
* Follow further actions done by the account.

</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 by asking a question.

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://cortex-docs.paloaltonetworks.com/analytics-alerts/alerts-by-name/possible-multistage-attack-in-microsoft-teams.md?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

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.