Detection rules › Splunk
Windows Disable or Modify Tools Via Taskkill
The following analytic identifies the use of taskkill.exe to forcibly terminate processes. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions that include specific taskkill parameters. This activity is significant because it can indicate attempts to disable security tools or disrupt legitimate applications, a common tactic in malware operations. If confirmed malicious, this behavior could allow attackers to evade detection, disrupt system stability, and potentially gain further control over the compromised system.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Defense Impairment | T1685 Disable or Modify Tools |
Event coverage
| Provider | Event | Title |
|---|---|---|
| Sysmon | Event ID 1 | Process creation |
| Security-Auditing | Event ID 4688 | A new process has been created. |
Rule body splunk
name: Windows Disable or Modify Tools Via Taskkill
id: a43ae66f-c410-4b3d-8741-9ce1ad17ddb0
version: 14
creation_date: '2023-09-19'
modification_date: '2026-05-13'
author: Teoderick Contreras, Splunk
status: production
type: Anomaly
description: The following analytic identifies the use of taskkill.exe to forcibly terminate processes. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions that include specific taskkill parameters. This activity is significant because it can indicate attempts to disable security tools or disrupt legitimate applications, a common tactic in malware operations. If confirmed malicious, this behavior could allow attackers to evade detection, disrupt system stability, and potentially gain further control over the compromised system.
data_source:
- Sysmon EventID 1
- Windows Event Log Security 4688
- CrowdStrike ProcessRollup2
search: |-
| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Processes
WHERE Processes.process_name = "taskkill.exe" Processes.process IN ("* /f*", "* /t*") Processes.process IN ("* /im*", "* /pid*")
BY Processes.action Processes.dest Processes.original_file_name
Processes.parent_process Processes.parent_process_exec Processes.parent_process_guid
Processes.parent_process_id Processes.parent_process_name Processes.parent_process_path
Processes.process Processes.process_exec Processes.process_guid
Processes.process_hash Processes.process_id Processes.process_integrity_level
Processes.process_name Processes.process_path Processes.user
Processes.user_id Processes.vendor_product
| `drop_dm_object_name("Processes")`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_disable_or_modify_tools_via_taskkill_filter`
how_to_implement: The detection is based on data that originates from Endpoint Detection and Response (EDR) agents. These agents are designed to provide security-related telemetry from the endpoints where the agent is installed. To implement this search, you must ingest logs that contain the process GUID, process name, and parent process. Additionally, you must ingest complete command-line executions. These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to the EDR product. The logs must also be mapped to the `Processes` node of the `Endpoint` data model. Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process.
known_false_positives: Network administrator can use this application to kill process during audit or investigation.
references:
- https://malpedia.caad.fkie.fraunhofer.de/details/win.njrat
drilldown_searches:
- name: View the detection results for - "$dest$"
search: '%original_detection_search% | search dest = "$dest$"'
earliest_offset: $info_min_time$
latest_offset: $info_max_time$
- name: View risk events for the last 7 days for - "$dest$"
search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$") | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`'
earliest_offset: 7d
latest_offset: "0"
intermediate_findings:
entities:
- field: dest
type: system
score: 20
message: A taskkill process to terminate process is executed on host- $dest$
threat_objects:
- field: parent_process_name
type: parent_process_name
analytic_story:
- PXA Stealer
- NjRAT
- Crypto Stealer
- BlankGrabber Stealer
asset_type: Endpoint
mitre_attack_id:
- T1685
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
category: endpoint
security_domain: endpoint
tests:
- name: True Positive Test
attack_data:
- data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1562.001/taskkill/taskkill_im.log
source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
sourcetype: XmlWinEventLog
test_type: unit
Stages and Predicates
Stage 1: tstats
| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Processes
WHERE Processes.process_name = "taskkill.exe" Processes.process IN ("* /f*", "* /t*") Processes.process IN ("* /im*", "* /pid*")
BY Processes.action Processes.dest Processes.original_file_name
Processes.parent_process Processes.parent_process_exec Processes.parent_process_guid
Processes.parent_process_id Processes.parent_process_name Processes.parent_process_path
Processes.process Processes.process_exec Processes.process_guid
Processes.process_hash Processes.process_id Processes.process_integrity_level
Processes.process_name Processes.process_path Processes.user
Processes.user_id Processes.vendor_product
Stage 2: search
| `drop_dm_object_name("Processes")`
Stage 3: search
| `security_content_ctime(firstTime)`
Stage 4: search
| `security_content_ctime(lastTime)`
Stage 5: search
| `windows_disable_or_modify_tools_via_taskkill_filter`
Indicators
Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.
| Field | Kind | Values |
|---|---|---|
Processes.process | in |
|
Processes.process_name | eq |
|