The following analytic identifies excessive usage of
icacls.exe application to change file or folder permission. This behavior is commonly seen where the adversary attempts to impair some users from deleting or accessing its malware components or artifact from the compromised system.
- Type: Anomaly
- Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Datamodel: Endpoint- Datasource: Splunk Add-on for Sysmon
- Last Updated: 2021-05-07
- Author: Teoderick Contreras, Splunk
- ID: 0bdf6092-af17-11eb-939a-acde48001122
|T1222||File and Directory Permissions Modification||Defense Evasion|
Kill Chain Phase
1 2 3 4 5 6 7 | tstats `security_content_summariesonly` values(Processes.process) as process values(Processes.process_id) as process_id values(Processes.process_name) as process_name count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.process_name = "cacls.exe" OR Processes.process_name = "icacls.exe" OR Processes.process_name = "XCACLS.exe" by Processes.parent_process_name Processes.parent_process 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_cacls_app_filter`
The SPL above uses the following Macros:
Note that excessive_usage_of_cacls_app_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
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
Known False Positives
Administrators or administrative scripts may use this application. Filter as needed.
Associated Analytic story
|80.0||80||100||An excessive amount of $process_name$ was executed on $dest$ attempting to modify permissions.|
source | version: 1