Files
splunk-security_content/detections/endpoint/linux_doas_tool_execution.yml
2024-06-26 14:41:53 +00:00

75 lines
3.1 KiB
YAML

name: Linux Doas Tool Execution
id: d5a62490-6e09-11ec-884e-acde48001122
version: 2
date: '2024-05-22'
author: Teoderick Contreras, Splunk
status: production
type: Anomaly
description: The following analytic detects the execution of the 'doas' tool on a
Linux host. This tool allows standard users to perform tasks with root privileges,
similar to 'sudo'. The detection leverages data from Endpoint Detection and Response
(EDR) agents, focusing on process names and command-line executions. This activity
is significant as 'doas' can be exploited by adversaries to gain elevated privileges
on a compromised host. If confirmed malicious, this could lead to unauthorized administrative
access, potentially compromising the entire system.
data_source:
- Sysmon for Linux EventID 1
search: '| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time)
as lastTime from datamodel=Endpoint.Processes where Processes.process_name = "doas"
by Processes.dest Processes.user Processes.parent_process_name Processes.process_name
Processes.process Processes.process_id Processes.parent_process_id Processes.process_guid
| `drop_dm_object_name(Processes)` | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`
| `linux_doas_tool_execution_filter`'
how_to_implement: 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: Administrator or network operator can execute this command.
Please update the filter macros to remove false positives.
references:
- https://wiki.gentoo.org/wiki/Doas
- https://www.makeuseof.com/how-to-install-and-use-doas/
tags:
analytic_story:
- Linux Privilege Escalation
- Linux Persistence Techniques
asset_type: Endpoint
confidence: 70
impact: 70
message: A doas $process_name$ with commandline $process$ was executed on $dest$
mitre_attack_id:
- T1548.003
- T1548
observable:
- name: dest
type: Hostname
role:
- Victim
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
required_fields:
- _time
- Processes.dest
- Processes.user
- Processes.parent_process_name
- Processes.process_name
- Processes.process
- Processes.process_id
- Processes.parent_process_id
risk_score: 49
security_domain: endpoint
tests:
- name: True Positive Test
attack_data:
- data:
https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1548.003/doas_exec/sysmon_linux.log
source: Syslog:Linux-Sysmon/Operational
sourcetype: sysmon:linux