Registry Persistence via AppInit DLL

Attackers may maintain persistence by creating registry keys using AppInit DLLs. AppInit DLLs are loaded by every process using the common library user32.dll.

Rule type: eql

Rule indices:

winlogbeat-*
logs-endpoint.events.*
logs-windows.*

Severity: medium

Risk score: 47

Runs every: 5m

Searches indices from: now-9m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

References: None

Tags:

Elastic
Host
Windows
Threat Detection
Persistence

Version: 4

Rule authors:

Elastic

Rule license: Elastic License v2

Investigation guide

edit

## Config

If enabling an EQL rule on a non-elastic-agent index (such as beats) for versions <8.2, events will not define `event.ingested` and default fallback for EQL rules was not added until 8.2, so you will need to add a custom pipeline to populate `event.ingested` to @timestamp for this rule to work.

Rule query

edit

registry where
   registry.path : ("HKLM\\SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\Windows\\AppInit_Dlls",
                    "HKLM\\SOFTWARE\\Wow6432Node\\Microsoft\\Windows NT\\CurrentVersion\\Windows\\AppInit_Dlls") and
   not process.executable : ("C:\\Windows\\System32\\msiexec.exe",
                             "C:\\Windows\\SysWOW64\\msiexec.exe",
                             "C:\\Program Files\\Commvault\\ContentStore*\\Base\\cvd.exe",
                             "C:\\Program Files (x86)\\Commvault\\ContentStore*\\Base\\cvd.exe")

Framework: MITRE ATT&CK^TM

Tactic:
- Name: Persistence
- ID: TA0003
- Reference URL: https://attack.mitre.org/tactics/TA0003/
Technique:
- Name: Event Triggered Execution
- ID: T1546
- Reference URL: https://attack.mitre.org/techniques/T1546/
Sub-technique:
- Name: AppInit DLLs
- ID: T1546.010
- Reference URL: https://attack.mitre.org/techniques/T1546/010/

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