Recon AVProduct Through Pwh or WMI

Try in Splunk Security Cloud

Description

The following analytic detects suspicious PowerShell script execution via EventCode 4104, specifically targeting checks for installed anti-virus products using WMI or PowerShell commands. This detection leverages PowerShell Script Block Logging to identify scripts containing keywords like "SELECT," "WMIC," "AntiVirusProduct," or "AntiSpywareProduct." This activity is significant as it is commonly used by malware and APT actors to map running security applications or services, potentially aiding in evasion techniques. If confirmed malicious, this could allow attackers to disable or bypass security measures, leading to further compromise of the endpoint.

• Type: TTP

• Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud

• Last Updated: 2024-05-21
• Author: Teoderick Contreras, Splunk
• ID: 28077620-c9f6-11eb-8785-acde48001122

Annotations

ATT&CK

ATT&CK

ID	Technique	Tactic
T1592	Gather Victim Host Information	Reconnaissance

Kill Chain Phase

• Reconnaissance

NIST

• DE.CM

CIS20

• CIS 10

CVE

Search

`powershell` EventCode=4104 (ScriptBlockText = "*SELECT*" OR ScriptBlockText = "*WMIC*") AND (ScriptBlockText = "*AntiVirusProduct*" OR ScriptBlockText = "*AntiSpywareProduct*") 
| 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)` 
| `recon_avproduct_through_pwh_or_wmi_filter`

Macros

The SPL above uses the following Macros:

• powershell
• security_content_ctime

recon_avproduct_through_pwh_or_wmi_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Required fields

List of fields required to use this analytic.

• _time
• EventCode
• ScriptBlockText
• Computer
• UserID

How To Implement

To successfully implement this analytic, you will need to enable PowerShell Script Block Logging on some or all endpoints. Additional setup here https://docs.splunk.com/Documentation/UBA/5.0.4.1/GetDataIn/AddPowerShell#Configure_module_logging_for_PowerShell.

Known False Positives

network administrator may used this command for checking purposes

Associated Analytic Story

• Qakbot
• Windows Post-Exploitation
• Hermetic Wiper
• Ransomware
• Prestige Ransomware
• Malicious PowerShell
• Data Destruction

RBA

Risk Score	Impact	Confidence	Message
56.0	70	80	A suspicious powershell script contains AV recon command on host $dest$

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://news.sophos.com/en-us/2020/05/12/maze-ransomware-1-year-counting/
• https://docs.splunk.com/Documentation/UBA/5.0.4.1/GetDataIn/AddPowerShell#Configure_module_logging_for_PowerShell.
• https://blog.palantir.com/tampering-with-windows-event-tracing-background-offense-and-defense-4be7ac62ac63
• https://static1.squarespace.com/static/552092d5e4b0661088167e5c/t/59c1814829f18782e24f1fe2/1505853768977/Windows+PowerShell+Logging+Cheat+Sheet+ver+Sept+2017+v2.1.pdf
• https://www.crowdstrike.com/blog/investigating-powershell-command-and-script-logging/
• https://www.splunk.com/en_us/blog/security/hunting-for-malicious-powershell-using-script-block-logging.html

Test Dataset

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

source | version: 3