The following analytic utilizes Windows Security Event ID 1102 or System log event 104 to identify when a Windows event log is cleared. Note that this analytic will require tuning or restricted to specific endpoints based on criticality. During triage, based on time of day and user, determine if this was planned. If not planned, follow through with reviewing parallel alerts and other data sources to determine what else may have occurred.
- Type: TTP
Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Last Updated: 2020-07-06
- Author: Rico Valdez, Michael Haag, Splunk
- ID: ad517544-aff9-4c96-bd99-d6eb43bfbb6a
Kill Chain Phase
- CIS 10
1 2 3 4 5 (`wineventlog_security` EventCode=1102) OR (`wineventlog_system` EventCode=104) | stats count min(_time) as firstTime max(_time) as lastTime by dest Message EventCode | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `windows_event_log_cleared_filter`
The SPL above uses the following Macros:
windows_event_log_cleared_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
List of fields required to use this analytic.
How To Implement
To successfully implement this search, you need to be ingesting Windows event logs from your hosts. In addition, the Splunk Windows TA is needed.
Known False Positives
It is possible that these logs may be legitimately cleared by Administrators. Filter as needed.
Associated Analytic Story
|70.0||70||100||Windows event logs cleared on $dest$ via EventCode $EventCode$|
The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.
source | version: 6