This analytic is designed to identify a high frequency of process termination events on a computer in a short period of time, which is a common behavior of ransomware malware before encrypting files. This technique is designed to avoid an exception error while accessing (docs, images, database and etc..) in the infected machine for encryption.
- Type: Anomaly
- Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Datamodel: Endpoint
- Last Updated: 2022-09-14
- Author: Teoderick Contreras
- ID: 17cd75b2-8666-11eb-9ab4-acde48001122
Kill Chain Phase
1 2 3 4 5 6 7 `sysmon` EventCode=5 |bin _time span=3s |stats values(Image) as proc_terminated min(_time) as firstTime max(_time) as lastTime count by _time Computer EventCode ProcessID | where count >= 15 | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)` | `high_process_termination_frequency_filter`
The SPL above uses the following Macros:
high_process_termination_frequency_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 logs with the Image (process full path of terminated process) from your endpoints. If you are using Sysmon, you must have at least version 6.0.4 of the Sysmon TA.
Known False Positives
admin or user tool that can terminate multiple process.
Associated Analytic Story
|72.0||90||80||High frequency process termination (more than 15 processes within 3s) detected on host $Computer$|
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: 2