ICACLS Grant Command
Description
The following analytic detects the use of the ICACLS command to grant additional access permissions to files or directories. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on specific process names and command-line arguments. This activity is significant because it is commonly used by Advanced Persistent Threats (APTs) and coinminer scripts to evade detection and maintain control over compromised systems. If confirmed malicious, this behavior could allow attackers to manipulate file permissions, potentially leading to unauthorized access, data exfiltration, or further system compromise.
Query · spl
| tstats `security_content_summariesonly` min(_time) as firstTime max(_time)
as lastTime from datamodel=Endpoint.Processes where
Processes.process_name IN ( "icacls.exe", "cacls.exe", "xcacls.exe") AND
Processes.process IN ("*/grant*", "*/g:*", "*/g *")
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)`
| `icacls_grant_command_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.