name: Eventvwr UAC Bypass
id: 9cf8fe08-7ad8-11eb-9819-acde48001122
version: 1
date: '2021-03-01'
author: Michael Haag, Splunk
type: batch
datamodel:
- Endpoint
description: The following search identifies Eventvwr bypass by identifying the registry
  modification into a specific path that eventvwr.msc looks to (but is not valid)
  upon execution. A successful attack will include a suspicious command to be executed
  upon eventvwr.msc loading. Upon triage, review the parallel processes that have
  executed. Identify any additional registry modifications on the endpoint that may
  look suspicious. Remediate as necessary.
search: '| tstats `security_content_summariesonly` count values(Registry.registry_key_name)
  as registry_key_name values(Registry.registry_path) as registry_path min(_time)
  as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Registry where  Registry.registry_path="*mscfile\\shell\\open\\command\\*"  by
  Registry.user, Registry.dest , Registry.registry_value_name| `security_content_ctime(lastTime)`
  | `security_content_ctime(firstTime)` | `drop_dm_object_name(Registry)` | `eventvwr_uac_bypass_filter`'
how_to_implement: To successfully implement this search you need to be ingesting information
  on process that include the name of the process responsible for the changes from
  your endpoints into the `Endpoint` datamodel in the `Registry` node.
known_false_positives: Some false positives may be present and will need to be filtered.
references:
- https://blog.malwarebytes.com/malwarebytes-news/2021/02/lazyscripter-from-empire-to-double-rat/
- https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1548.002/T1548.002.md
- https://attack.mitre.org/techniques/T1548/002
- https://enigma0x3.net/2016/08/15/fileless-uac-bypass-using-eventvwr-exe-and-registry-hijacking/
tags:
  analytic_story:
  - Windows Defense Evasion Tactics
  automated_detection_testing: passed
  dataset:
  - https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1548.002/atomic_red_team/windows-sysmon.log
  kill_chain_phases:
  - Exploitation
  - Privilege Escalation
  mitre_attack_id:
  - T1548.002
  product:
  - Splunk Enterprise
  - Splunk Enterprise Security
  - Splunk Cloud
  required_fields:
  - _time
  - Registry.registry_key_name
  - Registry.registry_path
  - Registry.user
  - Registry.dest
  - Registry.registry_value_name
  security_domain: endpoint
