ID | Technique | Tactic |
---|---|---|
T1112 | Modify Registry | Defense Evasion |
Detection: Windows Modify Registry Suppress Win Defender Notif
Description
The following analytic detects modifications in the Windows registry to suppress Windows Defender notifications. It leverages data from the Endpoint.Registry datamodel, specifically targeting changes to the "Notification_Suppress" registry value. This activity is significant because adversaries, including those deploying Azorult malware, use this technique to bypass Windows Defender and disable critical notifications. If confirmed malicious, this behavior could allow attackers to evade detection, maintain persistence, and execute further malicious activities without alerting the user or security tools.
Search
1
2| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Registry where Registry.registry_path= "*\\Windows Defender\\UX Configuration\\Notification_Suppress*" Registry.registry_value_data="0x00000001" by Registry.registry_key_name Registry.user Registry.registry_path Registry.registry_value_data Registry.action Registry.dest
3| `drop_dm_object_name(Registry)`
4| `security_content_ctime(firstTime)`
5| `security_content_ctime(lastTime)`
6| `windows_modify_registry_suppress_win_defender_notif_filter`
Data Source
Name | Platform | Sourcetype | Source | Supported App |
---|---|---|---|---|
Sysmon EventID 12 | Windows | 'xmlwineventlog' |
'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational' |
N/A |
Macros Used
Name | Value |
---|---|
security_content_ctime | convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$) |
windows_modify_registry_suppress_win_defender_notif_filter | search * |
windows_modify_registry_suppress_win_defender_notif_filter
is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
Annotations
Default Configuration
This detection is configured by default in Splunk Enterprise Security to run with the following settings:
Setting | Value |
---|---|
Disabled | true |
Cron Schedule | 0 * * * * |
Earliest Time | -70m@m |
Latest Time | -10m@m |
Schedule Window | auto |
Creates Risk Event | True |
Implementation
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 Registry
node. Also make sure that this registry was included in your config files ex. sysmon config to be monitored.
Known False Positives
administrators may enable or disable this feature that may cause some false positive.
Associated Analytic Story
Risk Based Analytics (RBA)
Risk Message | Risk Score | Impact | Confidence |
---|---|---|---|
the registry for suppresing windows fdefender notification settings was modified to disabled in $dest$ | 49 | 70 | 70 |
References
Detection Testing
Test Type | Status | Dataset | Source | Sourcetype |
---|---|---|---|---|
Validation | ✅ Passing | N/A | N/A | N/A |
Unit | ✅ Passing | Dataset | XmlWinEventLog:Microsoft-Windows-Sysmon/Operational |
xmlwineventlog |
Integration | ✅ Passing | Dataset | XmlWinEventLog:Microsoft-Windows-Sysmon/Operational |
xmlwineventlog |
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: GitHub | Version: 2