Windows Modify Registry Disable WinDefender Notifications
Description
The following analytic detects a suspicious registry modification aimed at disabling Windows Defender notifications. It leverages data from the Endpoint.Registry data model, specifically looking for changes to the registry path "*\SOFTWARE\Policies\Microsoft\Windows Defender Security Center\Notifications\DisableNotifications" with a value of "0x00000001". This activity is significant as it indicates an attempt to evade detection by disabling security alerts, a technique used by adversaries and malware like RedLine Stealer. If confirmed malicious, this could allow attackers to operate undetected, increasing the risk of further compromise and data exfiltration.
- Type: TTP
- Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Datamodel: Endpoint
- Last Updated: 2024-05-09
- Author: Teoderick Contreras, Splunk
- ID: 8e207707-ad40-4eb3-b865-3a52aec91f26
Annotations
Kill Chain Phase
- Exploitation
NIST
- DE.CM
CIS20
- CIS 10
CVE
Search
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| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Registry where Registry.registry_path="*\\SOFTWARE\\Policies\\Microsoft\\Windows Defender Security Center\\Notifications\\DisableNotifications" AND Registry.registry_value_data="0x00000001" by Registry.dest Registry.user Registry.registry_path Registry.registry_value_data Registry.registry_key_name
| `drop_dm_object_name(Registry)`
| `security_content_ctime(lastTime)`
| `security_content_ctime(firstTime)`
| `windows_modify_registry_disable_windefender_notifications_filter`
Macros
The SPL above uses the following Macros:
windows_modify_registry_disable_windefender_notifications_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
- Registry.registry_key_name
- Registry.registry_path
- Registry.user
- Registry.dest
- Registry.registry_value_name
- Registry.action
- Registry.registry_value_data
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
administrators may enable or disable this feature that may cause some false positive.
Associated Analytic Story
RBA
Risk Score | Impact | Confidence | Message |
---|---|---|---|
49.0 | 70 | 70 | A registry modification to disable Windows Defender notification on $dest$ |
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
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: 2