This search looks for process names that consist only of a single letter.
- Type: TTP
- Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
- Datamodel: Endpoint
- Last Updated: 2020-12-08
- Author: David Dorsey, Splunk
- ID: a4214f0b-e01c-41bc-8cc4-d2b71e3056b4
| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes by Processes.dest, Processes.user, Processes.process, Processes.process_name | `drop_dm_object_name(Processes)` | `security_content_ctime(lastTime)` | `security_content_ctime(firstTime)` | eval process_name_length = len(process_name), endExe = if(substr(process_name, -4) == ".exe", 1, 0) | search process_name_length=5 AND endExe=1 | table count, firstTime, lastTime, dest, user, process, process_name | `single_letter_process_on_endpoint_filter`
Associated Analytic Story
How To Implement
You must be ingesting data that records process activity from your hosts to populate the Endpoint data model in the Processes node. You must also be ingesting logs with both the process name and command line from your endpoints. The command-line arguments are mapped to the "process" field in the Endpoint data model.
Kill Chain Phase
- Actions on Objectives
Known False Positives
Single-letter executables are not always malicious. Investigate this activity with your normal incident-response process.
|63.0||70||90||A suspicious process $process_name$ with single letter in host $dest$|
source | version: 3