Disable Windows Behavior Monitoring
Description
The following analytic identifies modifications in the registry to disable Windows Defender's real-time behavior monitoring. It leverages data from the Endpoint.Registry data model, specifically monitoring changes to registry paths associated with Windows Defender settings. This activity is significant because disabling real-time protection is a common tactic used by malware such as RATs, bots, or Trojans to evade detection. If confirmed malicious, this action could allow an attacker to execute code, escalate privileges, or persist in the environment without being detected by antivirus software.
- Type: TTP
- Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Datamodel: Endpoint
- Last Updated: 2024-05-18
- Author: Steven Dick, Teoderick Contreras, Splunk
- ID: 79439cae-9200-11eb-a4d3-acde48001122
Annotations
ATT&CK
Kill Chain Phase
- Exploitation
NIST
- DE.CM
CIS20
- CIS 10
CVE
Search
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| tstats `security_content_summariesonly` count FROM datamodel=Endpoint.Registry WHERE (Registry.registry_path= "*\\SOFTWARE\\Policies\\Microsoft\\Windows Defender\\Real-Time Protection\\DisableBehaviorMonitoring" OR Registry.registry_path= "*\\SOFTWARE\\Policies\\Microsoft\\Windows Defender\\Real-Time Protection\\DisableOnAccessProtection" OR Registry.registry_path= "*\\SOFTWARE\\Policies\\Microsoft\\Windows Defender\\Real-Time Protection\\DisableScanOnRealtimeEnable" OR Registry.registry_path= "*\\SOFTWARE\\Microsoft\\Windows Defender\\Real-Time Protection\\DisableRealtimeMonitoring" OR Registry.registry_path= "*\\Real-Time Protection\\DisableIntrusionPreventionSystem" OR Registry.registry_path= "*\\Real-Time Protection\\DisableIOAVProtection" OR Registry.registry_path= "*\\Real-Time Protection\\DisableScriptScanning" AND Registry.registry_value_data = "0x00000001") BY _time span=1h Registry.dest Registry.user Registry.registry_path Registry.registry_key_name Registry.registry_value_name Registry.registry_value_data Registry.process_guid
| `drop_dm_object_name(Registry)`
| where isnotnull(registry_value_data)
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `disable_windows_behavior_monitoring_filter`
Macros
The SPL above uses the following Macros:
disable_windows_behavior_monitoring_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.dest
- Registry.registry_value_name
- Registry.registry_key_name
- Registry.registry_path
- Registry.registry_value_data
- Registry.process_guid
How To Implement
To successfully implement this search, you need to be ingesting logs with the registry value name, registry path, and registry value data from your endpoints. If you are using Sysmon, you must have at least version 2.0 of the offical Sysmon TA. https://splunkbase.splunk.com/app/5709
Known False Positives
admin or user may choose to disable this windows features.
Associated Analytic Story
- Azorult
- Ransomware
- Windows Registry Abuse
- RedLine Stealer
- Windows Defense Evasion Tactics
- CISA AA23-347A
- Revil Ransomware
RBA
Risk Score | Impact | Confidence | Message |
---|---|---|---|
40.0 | 40 | 100 | Windows Defender real time behavior monitoring disabled 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: 6