LoFP LoFP / it is possible there will be false positives, filter as needed.

Techniques

Sample rules

Windows ClipBoard Data via Get-ClipBoard

Description

The following analytic identifies a powershell script command to retrieve clipboard data. This technique was seen in several post exploitation tools like WINPEAS to steal sensitive information that was saved in clipboard. Using the Get-Clipboard powershell commandlet, adversaries can be able collect data stored in clipboard that might be a copied user name, password or other sensitive information.

Detection logic

`powershell` EventCode=4104 ScriptBlockText = "*Get-Clipboard*" 
| stats count min(_time) as firstTime max(_time) as lastTime by EventCode ScriptBlockText Computer UserID 
| rename Computer as dest 
| rename UserID as user
| `security_content_ctime(firstTime)` 
| `security_content_ctime(lastTime)` 
| `windows_clipboard_data_via_get_clipboard_filter`

PowerShell Domain Enumeration

Description

The following analytic utilizes PowerShell Script Block Logging (EventCode=4104) to identify suspicious PowerShell execution. Script Block Logging captures the command sent to PowerShell, the full command to be executed. Upon enabling, logs will output to Windows event logs. Dependent upon volume, enable on critical endpoints or all.

This analytic identifies specific PowerShell modules typically used to enumerate an organizations domain or users. During triage, review parallel processes using an EDR product or 4688 events. It will be important to understand the timeline of events around this activity. Review the entire logged PowerShell script block.

Detection logic

`powershell` EventCode=4104 ScriptBlockText IN (*get-netdomaintrust*, *get-netforesttrust*, *get-addomain*, *get-adgroupmember*, *get-domainuser*) 
| stats count min(_time) as firstTime max(_time) as lastTime by Computer EventCode ScriptBlockText UserID 
| rename Computer as dest 
| rename UserID as user 
| `security_content_ctime(firstTime)` 
| `security_content_ctime(lastTime)` 
| `powershell_domain_enumeration_filter`