Excessive Usage Of Taskkill
Description
The following analytic identifies excessive usage of taskkill.exe, a command-line utility used to terminate processes. The detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on instances where taskkill.exe is executed ten or more times within a one-minute span. This behavior is significant as adversaries often use taskkill.exe to disable security tools or other critical processes to evade detection. If confirmed malicious, this activity could allow attackers to bypass security defenses, maintain persistence, and further compromise the system.
Query · spl
| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime values(Processes.action) as action values(Processes.dest) as dest values(Processes.original_file_name) as original_file_name values(Processes.parent_process) as parent_process values(Processes.parent_process_exec) as parent_process_exec values(Processes.parent_process_guid) as parent_process_guid values(Processes.parent_process_id) as parent_process_id values(Processes.parent_process_path) as parent_process_path values(Processes.process) as process values(Processes.process_exec) as process_exec values(Processes.process_guid) as process_guid values(Processes.process_hash) as process_hash values(Processes.process_id) as process_id values(Processes.process_integrity_level) as process_integrity_level values(Processes.process_path) as process_path values(Processes.user) as user values(Processes.user_id) as user_id values(Processes.vendor_product) as vendor_product FROM datamodel=Endpoint.Processes
WHERE Processes.process_name = "taskkill.exe"
BY Processes.parent_process_name Processes.process_name Processes.dest
Processes.user _time span=1m
| where count >=10
| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `excessive_usage_of_taskkill_filter`
Implementation guide
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
- No false positives have been identified at this time.
Analyst notes
Known false positives: No false positives have been identified at this time.