Detection rules › Splunk
Disabling Task Manager
The following analytic identifies modifications to the Windows registry that disable Task Manager. It leverages data from the Endpoint.Registry data model, specifically looking for changes to the registry path "*\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\DisableTaskMgr" with a value of "0x00000001". This activity is significant as it is commonly associated with malware such as RATs, Trojans, and worms, which disable Task Manager to prevent users from terminating malicious processes. If confirmed malicious, this could allow attackers to maintain persistence and control over the infected system.
Known false positives
- admin may disable this application for non technical user.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Defense Impairment |
Telemetry coverage
| Provider | Record / event type |
|---|---|
| Sysmon | Event ID 13: RegistryEvent (Value Set) |
Rule body
name: Disabling Task Manager
id: dac279bc-9202-11eb-b7fb-acde48001122
version: 16
creation_date: '2021-03-31'
modification_date: '2026-05-13'
author: Teoderick Contreras, Splunk, Steven Dick
status: production
type: TTP
description: The following analytic identifies modifications to the Windows registry that disable Task Manager. It leverages data from the Endpoint.Registry data model, specifically looking for changes to the registry path "*\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Policies\\System\\DisableTaskMgr" with a value of "0x00000001". This activity is significant as it is commonly associated with malware such as RATs, Trojans, and worms, which disable Task Manager to prevent users from terminating malicious processes. If confirmed malicious, this could allow attackers to maintain persistence and control over the infected system.
data_source:
- Sysmon EventID 13
search: '| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Registry WHERE (Registry.registry_path= "*\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Policies\\System\\DisableTaskMgr" Registry.registry_value_data = "0x00000001") by Registry.action Registry.dest Registry.process_guid Registry.process_id Registry.registry_hive Registry.registry_path Registry.registry_key_name Registry.registry_value_data Registry.registry_value_name Registry.registry_value_type Registry.status Registry.user Registry.vendor_product | `drop_dm_object_name(Registry)` | where isnotnull(registry_value_data) | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `disabling_task_manager_filter`'
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 official Sysmon TA. https://splunkbase.splunk.com/app/5709
known_false_positives: admin may disable this application for non technical user.
references:
- https://any.run/report/ea4ea08407d4ee72e009103a3b77e5a09412b722fdef67315ea63f22011152af/a866d7b1-c236-4f26-a391-5ae32213dfc4#registry
- https://blog.talosintelligence.com/2020/05/threat-roundup-0424-0501.html
finding:
title: The Windows Task Manager was disabled on $dest$ by $user$.
entity:
field: user
type: user
score: 50
intermediate_findings:
entities:
- field: dest
type: system
score: 50
message: The Windows Task Manager was disabled on $dest$ by $user$.
analytic_story:
- Windows Defense Evasion Tactics
- Windows Registry Abuse
- NjRAT
asset_type: Endpoint
mitre_attack_id:
- T1685
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
category: endpoint
security_domain: endpoint
Stages and Predicates
Stage 1: tstats
| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Registry WHERE (Registry.registry_path= "*\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Policies\\System\\DisableTaskMgr" Registry.registry_value_data = "0x00000001") by Registry.action Registry.dest Registry.process_guid Registry.process_id Registry.registry_hive Registry.registry_path Registry.registry_key_name Registry.registry_value_data Registry.registry_value_name Registry.registry_value_type Registry.status Registry.user Registry.vendor_product
Stage 2: search
| `drop_dm_object_name(Registry)`
Stage 3: where
| where isnotnull(registry_value_data)
Stage 4: search
| `security_content_ctime(firstTime)`
Stage 5: search
| `security_content_ctime(lastTime)`
Stage 6: search
| `disabling_task_manager_filter`
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
Registry.registry_path | eq |
| field:"registry_path" kind:eq |
Registry.registry_value_data | eq |
| field:"Details" kind:eq |
registry_value_data | is_not_null | field:"Details" kind:is_not_null |