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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.

  • Type: TTP
  • Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud
  • Datamodel: Endpoint
  • Last Updated: 2021-03-01
  • Author: Michael Haag, Splunk
  • ID: 9cf8fe08-7ad8-11eb-9819-acde48001122

ATT&CK

ID Technique Tactic
T1548.002 Bypass User Account Control Privilege Escalation, Defense Evasion
T1548 Abuse Elevation Control Mechanism Privilege Escalation, Defense Evasion

| 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`

Associated Analytic Story

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.

Required field

  • _time
  • Registry.registry_key_name
  • Registry.registry_path
  • Registry.user
  • Registry.dest
  • Registry.registry_value_name

Kill Chain Phase

  • Exploitation
  • Privilege Escalation

Known False Positives

Some false positives may be present and will need to be filtered.

RBA

Risk Score Impact Confidence Message
80.0 80 100 Registry values were modified to bypass UAC using Event Viewer on $dest$ by $user$.

Reference

Test Dataset

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

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