--- title: "Powershell Disable Security Monitoring" excerpt: "Disable or Modify Tools , Impair Defenses " categories: - Endpoint last_modified_at: 2022-07-15 toc: true toc_label: "" tags: - Disable or Modify Tools - Impair Defenses - Defense Evasion - Defense Evasion - Splunk Enterprise - Splunk Enterprise Security - Splunk Cloud - Endpoint --- [Try in Splunk Security Cloud](https://www.splunk.com/en_us/products/cyber-security.html){: .btn .btn--success} #### Description This search is to identifies a modification in registry to disable the windows denfender real time behavior monitoring. This event or technique is commonly seen in RAT, bot, or Trojan to disable AV to evade detections. - **Type**: [TTP](https://github.com/splunk/security_content/wiki/Detection-Analytic-Types) - **Product**: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud - **Datamodel**: [Endpoint](https://docs.splunk.com/Documentation/CIM/latest/User/Endpoint)- **Datasource**: [Splunk Add-on for Sysmon](https://splunkbase.splunk.com/app/5709) - **Last Updated**: 2022-07-15 - **Author**: Michael Haag, Splunk - **ID**: c148a894-dd93-11eb-bf2a-acde48001122 #### Annotations
ATT&CK
| ID | Technique | Tactic | | -------------- | ---------------- |-------------------- | | [T1562.001](https://attack.mitre.org/techniques/T1562/001/) | Disable or Modify Tools | Defense Evasion | | [T1562](https://attack.mitre.org/techniques/T1562/) | Impair Defenses | Defense Evasion |
Kill Chain Phase
* Exploitation
NIST
CIS20
CVE
#### Search ``` | tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where `process_powershell` Processes.process="*set-mppreference*" AND Processes.process IN ("*disablerealtimemonitoring*","*disableioavprotection*","*disableintrusionpreventionsystem*","*disablescriptscanning*","*disableblockatfirstseen*","*DisableBehaviorMonitoring*","*drtm *","*dioavp *","*dscrptsc *","*dbaf *","*dbm *") by Processes.dest Processes.user Processes.parent_process Processes.original_file_name Processes.process_name Processes.process Processes.process_id Processes.parent_process_id | `drop_dm_object_name(Processes)` | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `powershell_disable_security_monitoring_filter` ``` #### Macros The SPL above uses the following Macros: * [security_content_ctime](https://github.com/splunk/security_content/blob/develop/macros/security_content_ctime.yml) * [process_powershell](https://github.com/splunk/security_content/blob/develop/macros/process_powershell.yml) * [security_content_summariesonly](https://github.com/splunk/security_content/blob/develop/macros/security_content_summariesonly.yml) > :information_source: > **powershell_disable_security_monitoring_filter** is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL. #### Required field * _time * Processes.dest * Processes.user * Processes.parent_process_name * Processes.parent_process * Processes.original_file_name * Processes.process_name * Processes.process * Processes.process_id * Processes.parent_process_path * Processes.process_path * Processes.parent_process_id #### 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 Limited false positives. However, tune based on scripts that may perform this action. #### Associated Analytic story * [Ransomware](/stories/ransomware) * [Revil Ransomware](/stories/revil_ransomware) #### RBA | Risk Score | Impact | Confidence | Message | | ----------- | ----------- |--------------|--------------| | 25.0 | 50 | 50 | | > :information_source: > 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://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1562.001/T1562.001.md#atomic-test-15---tamper-with-windows-defender-atp-powershell](https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1562.001/T1562.001.md#atomic-test-15---tamper-with-windows-defender-atp-powershell) * [https://docs.microsoft.com/en-us/powershell/module/defender/set-mppreference?view=windowsserver2022-ps](https://docs.microsoft.com/en-us/powershell/module/defender/set-mppreference?view=windowsserver2022-ps) #### Test Dataset Replay any dataset to Splunk Enterprise by using our [replay.py](https://github.com/splunk/attack_data#using-replaypy) tool or the [UI](https://github.com/splunk/attack_data#using-ui). Alternatively you can replay a dataset into a [Splunk Attack Range](https://github.com/splunk/attack_range#replay-dumps-into-attack-range-splunk-server) * [https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1562.001/pwh_defender_disabling/windows-sysmon.log](https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1562.001/pwh_defender_disabling/windows-sysmon.log) [*source*](https://github.com/splunk/security_content/tree/develop/detections/endpoint/powershell_disable_security_monitoring.yml) \| *version*: **3**