Detection rules › Splunk

Runas Execution in CommandLine

Status
production
Group by
IntegrityLevel, command_line, computer_name, event_action, original_file_name, parent_command_line, parent_process_guid, parent_process_id, parent_process_name, process_guid, process_hash, process_id, process_name, user, user_id, vendor_product
Author
Teoderick Contreras, Splunk
Source
github.com/splunk/security_content

The following analytic detects the execution of the runas.exe process with administrator user options. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions and process details. This activity is significant as it may indicate an attempt to gain elevated privileges, a common tactic in privilege escalation and lateral movement. If confirmed malicious, this could allow an attacker to execute commands with higher privileges, potentially leading to unauthorized access, data exfiltration, or further compromise of the target host.

MITRE ATT&CK coverage

Event coverage

Rule body splunk

name: Runas Execution in CommandLine
id: 4807e716-43a4-11ec-a0e7-acde48001122
version: 10
creation_date: '2021-11-17'
modification_date: '2026-05-13'
author: Teoderick Contreras, Splunk
status: production
type: Hunting
description: The following analytic detects the execution of the runas.exe process with administrator user options. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on command-line executions and process details. This activity is significant as it may indicate an attempt to gain elevated privileges, a common tactic in privilege escalation and lateral movement. If confirmed malicious, this could allow an attacker to execute commands with higher privileges, potentially leading to unauthorized access, data exfiltration, or further compromise of the target host.
data_source:
    - Sysmon EventID 1
    - Windows Event Log Security 4688
    - CrowdStrike ProcessRollup2
search: |
    | tstats `security_content_summariesonly` count min(_time) as firstTime max(_time)
    as lastTime from datamodel=Endpoint.Processes where
    (Processes.process_name="runas.exe" OR Processes.original_file_name="runas.exe")
    Processes.process ="*/user:*"
    Processes.process = "*admin*"
    by Processes.action Processes.dest
       Processes.original_file_name Processes.parent_process Processes.parent_process_exec
       Processes.parent_process_guid Processes.parent_process_id Processes.parent_process_name
       Processes.parent_process_path Processes.process Processes.process_exec Processes.process_guid
       Processes.process_hash Processes.process_id Processes.process_integrity_level Processes.process_name
       Processes.process_path Processes.user Processes.user_id Processes.vendor_product
    | `drop_dm_object_name(Processes)`
    | `security_content_ctime(firstTime)`
    | `security_content_ctime(lastTime)`
    | `runas_execution_in_commandline_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: A network operator or systems administrator may utilize an automated or manual execute this command that may generate false positives. filter is needed.
references:
    - https://app.any.run/tasks/ad4c3cda-41f2-4401-8dba-56cc2d245488/
analytic_story:
    - Quasar RAT
    - Data Destruction
    - Windows Privilege Escalation
    - Hermetic Wiper
asset_type: Endpoint
mitre_attack_id:
    - T1134.001
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: endpoint
security_domain: endpoint
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/malware/vilsel/sysmon.log
          source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
          sourcetype: XmlWinEventLog
      test_type: unit

Stages and Predicates

Stage 1: tstats

| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time)
as lastTime from datamodel=Endpoint.Processes where
(Processes.process_name="runas.exe" OR Processes.original_file_name="runas.exe")
Processes.process ="*/user:*"
Processes.process = "*admin*"
by Processes.action Processes.dest
   Processes.original_file_name Processes.parent_process Processes.parent_process_exec
   Processes.parent_process_guid Processes.parent_process_id Processes.parent_process_name
   Processes.parent_process_path Processes.process Processes.process_exec Processes.process_guid
   Processes.process_hash Processes.process_id Processes.process_integrity_level Processes.process_name
   Processes.process_path Processes.user Processes.user_id Processes.vendor_product

Stage 2: search

| `drop_dm_object_name(Processes)`

Stage 3: search

| `security_content_ctime(firstTime)`

Stage 4: search

| `security_content_ctime(lastTime)`

Stage 5: search

| `runas_execution_in_commandline_filter`

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
Processes.original_file_nameeq
  • "runas.exe"
Processes.processeq
  • "*/user:*" corpus 7 (sigma 5, splunk 2)
  • "*admin*" corpus 4 (sigma 3, splunk 1)
Processes.process_nameeq
  • "runas.exe" corpus 2 (elastic 1, splunk 1)