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splunk-security_content/docs/_posts/2021-04-12-excel_spawning_powershell.md
2022-07-19 21:35:47 +00:00

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---
title: "Excel Spawning PowerShell"
excerpt: "Security Account Manager
, OS Credential Dumping
"
categories:
- Endpoint
last_modified_at: 2021-04-12
toc: true
toc_label: ""
tags:
- Security Account Manager
- OS Credential Dumping
- Credential Access
- Credential Access
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
- Endpoint
---
[Try in Splunk Security Cloud](https://www.splunk.com/en_us/products/cyber-security.html){: .btn .btn--success}
#### Description
The following detection identifies Microsoft Excel spawning PowerShell. Typically, this is not common behavior and not default with Excel.exe. Excel.exe will generally be found in the following path `C:\Program Files\Microsoft Office\root\Office16` (version will vary). PowerShell spawning from Excel.exe is common for a spearphishing attachment and is actively used. Albeit, the command executed will most likely be encoded and captured via another detection. During triage, review parallel processes and identify any files that may have been written.
- **Type**: [TTP](https://github.com/splunk/security_content/wiki/Detection-Analytic-Types)
- **Product**: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- **Datamodel**: [Endpoint](https://docs.splunk.com/Documentation/CIM/latest/User/Endpoint)- **Datasource**: [Splunk Add-on for Sysmon](https://splunkbase.splunk.com/app/5709)
- **Last Updated**: 2021-04-12
- **Author**: Michael Haag, Splunk
- **ID**: 42d40a22-9be3-11eb-8f08-acde48001122
#### Annotations
<details>
<summary>ATT&CK</summary>
<div markdown="1">
| ID | Technique | Tactic |
| -------------- | ---------------- |-------------------- |
| [T1003.002](https://attack.mitre.org/techniques/T1003/002/) | Security Account Manager | Credential Access |
| [T1003](https://attack.mitre.org/techniques/T1003/) | OS Credential Dumping | Credential Access |
</div>
</details>
<details>
<summary>Kill Chain Phase</summary>
<div markdown="1">
* Exploitation
</div>
</details>
<details>
<summary>NIST</summary>
<div markdown="1">
</div>
</details>
<details>
<summary>CIS20</summary>
<div markdown="1">
</div>
</details>
<details>
<summary>CVE</summary>
<div markdown="1">
</div>
</details>
#### Search
```
| tstats `security_content_summariesonly` count values(Processes.process) min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.parent_process_name="excel.exe" `process_powershell` by Processes.parent_process Processes.process_name Processes.user Processes.dest Processes.original_file_name
| `drop_dm_object_name("Processes")`
| `security_content_ctime(firstTime)`
|`security_content_ctime(lastTime)`
| `excel_spawning_powershell_filter`
```
#### Macros
The SPL above uses the following Macros:
* [security_content_ctime](https://github.com/splunk/security_content/blob/develop/macros/security_content_ctime.yml)
* [process_powershell](https://github.com/splunk/security_content/blob/develop/macros/process_powershell.yml)
* [security_content_summariesonly](https://github.com/splunk/security_content/blob/develop/macros/security_content_summariesonly.yml)
> :information_source:
> **excel_spawning_powershell_filter** is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
#### Required field
* Processes.dest
* Processes.user
* Processes.parent_process_name
* Processes.parent_process
* Processes.original_file_name
* Processes.process_name
* Processes.process
* Processes.process_id
* Processes.parent_process_path
* Processes.process_path
* Processes.parent_process_id
#### How To Implement
To successfully implement this search you need to be ingesting information on process that include the name of the process responsible for the changes from your endpoints into the `Endpoint` datamodel in the `Processes` node. In addition, confirm the latest CIM App 4.20 or higher is installed and the latest TA for the endpoint product.
#### Known False Positives
False positives should be limited, but if any are present, filter as needed.
#### Associated Analytic story
* [Spearphishing Attachments](/stories/spearphishing_attachments)
#### RBA
| Risk Score | Impact | Confidence | Message |
| ----------- | ----------- |--------------|--------------|
| 80.0 | 80 | 100 | An instance of $parent_process_name$ spawning $process_name$ was identified on endpoint $dest$ by user $user$, indicating potential suspicious macro execution. |
> :information_source:
> The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.
#### Reference
* [https://redcanary.com/threat-detection-report/techniques/powershell/](https://redcanary.com/threat-detection-report/techniques/powershell/)
* [https://attack.mitre.org/techniques/T1566/001/](https://attack.mitre.org/techniques/T1566/001/)
#### Test Dataset
Replay any dataset to Splunk Enterprise by using our [replay.py](https://github.com/splunk/attack_data#using-replaypy) tool or the [UI](https://github.com/splunk/attack_data#using-ui).
Alternatively you can replay a dataset into a [Splunk Attack Range](https://github.com/splunk/attack_range#replay-dumps-into-attack-range-splunk-server)
* [https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1566.001/macro/windows-sysmon.log](https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1566.001/macro/windows-sysmon.log)
[*source*](https://github.com/splunk/security_content/tree/develop/detections/endpoint/excel_spawning_powershell.yml) \| *version*: **1**