> 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/uncommon-network-tunnel-creation.md).

# Uncommon network tunnel creation

### Synopsis

| Field                | Value                        |
| -------------------- | ---------------------------- |
| Activation Period    | 14 Days                      |
| Training Period      | 30 Days                      |
| Test Period          | N/A (single event)           |
| Deduplication Period | 12 Hours                     |
| Required Data        | Palo Alto Networks Url Logs  |
| ATT\&CK Tactic       | Command and Control (TA0011) |
| ATT\&CK Technique    | Protocol Tunneling (T1572)   |
| Severity             | Informational                |

### Description

An uncommon network tunnel was established.

### Attacker's Goals

Attackers may use SSH or any similar utility to create a network tunnel to allow an attacker to covertly connect to an internal host.

### Investigative actions

* Review the external IP/domain using known intelligence tools.
* Investigate the causality of the process and its user ID to find uncommon behaviors.
* Search for processes or files that were created by this SSH instance.

### Variations

<details>

<summary>Uncommon network tunnel creation</summary>

**Synopsis**

| Field             | Value                        |
| ----------------- | ---------------------------- |
| ATT\&CK Tactic    | Command and Control (TA0011) |
| ATT\&CK Technique | Protocol Tunneling (T1572)   |
| Severity          | Informational                |

**Description**

An uncommon network tunnel was established using ACS\_ssh.exe.

**Attacker's Goals**

Attackers may use SSH or any similar utility to create a network tunnel to allow an attacker to covertly connect to an internal host.

**Investigative actions**

* Review the external IP/domain using known intelligence tools.
* Investigate the causality of the process and its user ID to find uncommon behaviors.
* Search for processes or files that were created by this SSH instance.

</details>

<details>

<summary>Uncommon SSH tunnel to unpopular IP address</summary>

**Synopsis**

| Field             | Value                        |
| ----------------- | ---------------------------- |
| ATT\&CK Tactic    | Command and Control (TA0011) |
| ATT\&CK Technique | Protocol Tunneling (T1572)   |
| Severity          | Low                          |

**Description**

An uncommon SSH tunnel was established to an unpopular remote IP address at the organization.

**Attacker's Goals**

Attackers may use SSH or any similar utility to create a network tunnel to allow an attacker to covertly connect to an internal host.

**Investigative actions**

* Review the external IP/domain using known intelligence tools.
* Investigate the causality of the process and its user ID to find uncommon behaviors.
* Search for processes or files that were created by this SSH instance.

</details>

<details>

<summary>An uncommon network tunnel was established over the default SSH port</summary>

**Synopsis**

| Field             | Value                        |
| ----------------- | ---------------------------- |
| ATT\&CK Tactic    | Command and Control (TA0011) |
| ATT\&CK Technique | Protocol Tunneling (T1572)   |
| Severity          | Low                          |

**Description**

An unpopular process and command line created a network tunnel over the default SSH port.

**Attacker's Goals**

Attackers may use SSH or any similar utility to create a network tunnel to allow an attacker to covertly connect to an internal host.

**Investigative actions**

* Review the external IP/domain using known intelligence tools.
* Investigate the causality of the process and its user ID to find uncommon behaviors.
* Search for processes or files that were created by this SSH instance.

</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/uncommon-network-tunnel-creation.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.