MediumSplunk security content Michael Haag +1Threat hunting

PowerShell 4104 Hunting

Description

The following analytic identifies suspicious PowerShell execution using Script Block Logging (EventCode 4104). It leverages specific patterns and keywords within the ScriptBlockText field to detect potentially malicious activities. This detection is significant for SOC analysts as PowerShell is commonly used by attackers for various malicious purposes, including code execution, privilege escalation, and persistence. If confirmed malicious, this activity could allow attackers to execute arbitrary commands, exfiltrate data, or maintain long-term access to the compromised system, posing a severe threat to the organization's security.

Detection logic

Detection requirements

Platform: Linux macOS Windows
The rule states no platform. This is derived from the 3 ATT&CK techniques it maps to.
Log source category: powershell_script_block_logging_4104

Known benign triggers

Limited false positives. May filter as needed.

References

Links the source published beside this detection. Reference is the link the source wrote, unmodified. Class is decided by this catalogue from the host and path, not stated by the source. Cited by counts published detections citing the same resource, including this one, and the sources beneath it count the repositories this catalogue ingests, which is not the same as independent research.
Reference	Class	Cited by
adlumin.com/post/powerdrop-a-new-insidious-powershell-script-for-command-and-control-attacks-targets-u-s-aerospace-defense-industry/	Unclassified	Only this detection cites it
devblogs.microsoft.com/powershell/powershell-the-blue-team/	Unclassified	Only this detection cites it
docs.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_logging?view=powershell-5.1	Product documentation	Only this detection cites it
github.com/inodee/threathunting-spl/blob/master/hunt-queries/powershell_qualifiers.md	Tool	Only this detection cites it
github.com/marcurdy/dfir-toolset/blob/master/Powershell%20Blueteam.txt	Tool	Only this detection cites it
help.splunk.com/en/security-offerings/splunk-user-behavior-analytics/get-data-in/5.4.1/add-other-data-to-splunk-uba/configure-powershell-logging-to-see-powershell-anomalies-in-splunk-uba	Product documentation	3
hurricanelabs.com/splunk-tutorials/how-to-use-powershell-transcription-logs-in-splunk/	Unclassified	Only this detection cites it
www.mandiant.com/resources/greater-visibilityt	Threat report	Only this detection cites it
www.splunk.com/en_us/blog/security/hunting-for-malicious-powershell-using-script-block-logging.html	Security research	14

Detection rules

PowerShell 4104 Hunting

Description

Detection logic

Detection requirements

Known benign triggers

MITRE ATT&CK mappings

References

From the source

Licence

Authorship

Detection rules