Powershell Enable SMB1Protocol Feature
Description
The following analytic detects the enabling of the SMB1 protocol via powershell.exe
. It leverages PowerShell script block logging (EventCode 4104) to identify the execution of the Enable-WindowsOptionalFeature
cmdlet with the SMB1Protocol
parameter. This activity is significant because enabling SMB1 can facilitate lateral movement and file encryption by ransomware, such as RedDot. If confirmed malicious, this action could allow an attacker to propagate through the network, encrypt files, and potentially disrupt business operations.
- Type: TTP
-
Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Last Updated: 2024-05-13
- Author: Teoderick Contreras, Splunk
- ID: afed80b2-d34b-11eb-a952-acde48001122
Annotations
ATT&CK
Kill Chain Phase
- Exploitation
NIST
- DE.CM
CIS20
- CIS 10
CVE
Search
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`powershell` EventCode=4104 ScriptBlockText = "*Enable-WindowsOptionalFeature*" ScriptBlockText = "*SMB1Protocol*"
| stats count min(_time) as firstTime max(_time) as lastTime by EventCode ScriptBlockText Computer UserID
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `powershell_enable_smb1protocol_feature_filter`
Macros
The SPL above uses the following Macros:
powershell_enable_smb1protocol_feature_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 search, you need to be ingesting logs with the powershell logs from your endpoints. make sure you enable needed registry to monitor this event.
Known False Positives
network operator may enable or disable this windows feature.
Associated Analytic Story
RBA
Risk Score | Impact | Confidence | Message |
---|---|---|---|
25.0 | 50 | 50 | Powershell Enable SMB1Protocol Feature on $Computer$ |
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://app.any.run/tasks/c0f98850-af65-4352-9746-fbebadee4f05/
- 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